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Sample records for 222rn exhalation ratio

  1. Exhalation of (222)Rn from phosphogypsum piles located at the Southwest of Spain.

    PubMed

    Dueñas, C; Liger, E; Cañete, S; Pérez, M; Bolívar, J P

    2007-01-01

    Phosphogypsum (PG) is a waste product of the phosphoric acid production process and contains, generally, high activity concentrations of uranium series radionuclides. It is stored in piles formed over the last 40 years close to the town of Huelva (Southwest of Spain). The very broad expanse of the PG piles (about 1200 ha) produces a local, but unambiguous, radioactive impact to their surroundings. In 1992, the regional government of Andalusia restored an area of 400 ha by covering it with a 25-cm thick layer of natural soil and, currently, there is an additional zone of 400 ha in course of restoration (unrestored) and the same area of active PG stacks. Due to the high activity concentration of (226)Ra in active PG stacks (average 647 Bq kg(-1)), a significant exhalation of (222)Rn could be produced from the surface of the piles. Measurements have been made of (222)Rn exhalation from active PG stacks and from restored and unrestored zones. The (222)Rn exhalation from unrestored zones is half of that of the active PG stacks. Following restoration, the (222)Rn exhalation is approximately eight times lower than the active PG stacks. The activity concentrations of natural radionuclides ((226)Ra, (40)K, (232)Th) in the mentioned zones have been determined. This study was also conducted to determine the effect of (226)Ra activity concentration on the (222)Rn exhalation, and a good correlation was obtained between the (222)Rn exhalation and (226)Ra activity, porosity and density of soil.

  2. A method to simultaneously and continuously measure the 222Rn and 220Rn exhalation rates of soil in an open loop.

    PubMed

    Tan, Yanliang; Xiao, Detao; Yuan, Hongzhi; Shan, Jian

    2014-01-01

    This paper presents a process in which a radon monitor based on the electrostatic collection method is used to measure the (222)Rn and (220)Rn exhalation rates simultaneously and continuously employing a ventilation-type accumulation chamber. Generally, the radon exhalation rate can be measured by accumulation technique, but cannot be measured continuously. The advantage of this method using a ventilation-type accumulation chamber is that the radon exhalation rates can be measured continuously. Even though the environmental air is drawn into the chamber, the low atmospheric values of radon and thoron do not influence the measurement accuracy. The (222)Rn and (220)Rn exhalation rates error from the environmental air is less than 5% in this experiment.

  3. Extensive radioactive characterization of a phosphogypsum stack in SW Spain: 226Ra, 238U, 210Po concentrations and 222Rn exhalation rate.

    PubMed

    Abril, José-María; García-Tenorio, Rafael; Manjón, Guillermo

    2009-05-30

    Phosphogypsum (PG) is a by-product of the phosphate fertilizer industries that contains relatively high concentrations of uranium series radionuclides. The US-EPA regulates the agriculture use of PG, attending to its (226)Ra content and to the (222)Rn exhalation rate from inactive stacks. Measurements of (222)Rn exhalation rates in PG stacks typically show a large and still poorly understood spatial and temporal variability, and the published data are scarce. This work studies an inactive PG stack in SW Spain of about 0.5 km(2) from where PG can be extracted for agriculture uses, and an agriculture soil 75 km apart, being representative of the farms to be amended with PG. Activity concentrations of (226)Ra, (238)U and (210)Po have been measured in 30 PG samples (0-90 cm horizon) allowing for the construction of maps with spatial distributions in the PG stack and for the characterization of the associated PG inputs to agriculture soils. Averaged (226)Ra concentrations for the stack were 730+/-60 Bq kg(-1) (d.w.), over the US-EPA limit of 370 Bq kg(-1). (222)Rn exhalation rate has been measured by the charcoal canister method in 49 sampling points with 3 canisters per sampling point. Values in PG stack were under the US-EPA limit of 2600 Bq m(-2)h(-1), but they were one order of magnitude higher than those found in the agriculture soil. Variability in radon emissions has been studied at different spatial scales. Radon exhalation rates were correlated with (226)Ra concentrations and daily potential evapotranspiration (ETo). They increased with ETo in agriculture soils, but showed an opposite behaviour in the PG stack.

  4. Inverse modeling of Asian (222)Rn flux using surface air (222)Rn concentration.

    PubMed

    Hirao, Shigekazu; Yamazawa, Hiromi; Moriizumi, Jun

    2010-11-01

    When used with an atmospheric transport model, the (222)Rn flux distribution estimated in our previous study using soil transport theory caused underestimation of atmospheric (222)Rn concentrations as compared with measurements in East Asia. In this study, we applied a Bayesian synthesis inverse method to produce revised estimates of the annual (222)Rn flux density in Asia by using atmospheric (222)Rn concentrations measured at seven sites in East Asia. The Bayesian synthesis inverse method requires a prior estimate of the flux distribution and its uncertainties. The atmospheric transport model MM5/HIRAT and our previous estimate of the (222)Rn flux distribution as the prior value were used to generate new flux estimates for the eastern half of the Eurasian continent dividing into 10 regions. The (222)Rn flux densities estimated using the Bayesian inversion technique were generally higher than the prior flux densities. The area-weighted average (222)Rn flux density for Asia was estimated to be 33.0 mBq m(-2) s(-1), which is substantially higher than the prior value (16.7 mBq m(-2) s(-1)). The estimated (222)Rn flux densities decrease with increasing latitude as follows: Southeast Asia (36.7 mBq m(-2) s(-1)); East Asia (28.6 mBq m(-2) s(-1)) including China, Korean Peninsula and Japan; and Siberia (14.1 mBq m(-2) s(-1)). Increase of the newly estimated fluxes in Southeast Asia, China, Japan, and the southern part of Eastern Siberia from the prior ones contributed most significantly to improved agreement of the model-calculated concentrations with the atmospheric measurements. The sensitivity analysis of prior flux errors and effects of locally exhaled (222)Rn showed that the estimated fluxes in Northern and Central China, Korea, Japan, and the southern part of Eastern Siberia were robust, but that in Central Asia had a large uncertainty.

  5. Relationships between 222Rn dissolved in ground water supplies and indoor 222Rn concentrations in some Colorado front range houses.

    PubMed

    Folger, P F; Nyberg, P; Wanty, R B; Poeter, E

    1994-09-01

    Indoor 222Rn concentrations were measured in 37 houses with alpha track detectors placed in water-use rooms near water sources (bathrooms, laundry rooms, and kitchens) and in non-water-use living rooms, dining rooms, and bedrooms away from water sources. Results show that relative contributions of 222Rn to indoor air from water use are insignificant when soil-gas concentrations are high but become increasingly important as the ratio of 222Rn-in-water: 222Rn-in-soil gas increases. High soil-gas 222Rn concentrations may mask 222Rn contributions from water even when waterborne 222Rn concentrations are as high as 750 kBq m-3. Ground water in Precambrian Pikes Peak granite averages 340 kBq m-3 222Rn, vs. 170 kBq m-3 in Precambrian migmatite, but average 222Rn concentrations in soil gas are also lower in migmatite. Because the ratio of 222Rn-in-water: 222Rn-in-soil gas may be consistently higher for houses in migmatite than in Pikes Peak granite, indoor air in houses built on migmatite may have a greater relative contribution from water use even though average 222Rn concentrations in the water are lower. Continuous monitoring of 222Rn concentrations in air on 15-min intervals also indicates that additions to indoor concentrations from water use are significant and measurable only when soil-gas concentrations are low and concentrations in water are high. When soil-gas concentrations were mitigated to less than 150 Bq m-3 in one house, water contributes 20-40% of the annual indoor 222Rn concentration in the laundry room (222Rn concentration in water of 670 kBq m-3). Conversely, when the mitigation system is inactive, diurnal fluctuations and other variations in the soil-gas 222Rn contribution swamp the variability due to water use in the house. Measurable variations in indoor concentrations from water use were not detected in one house despite a low soil-gas contribution of approximately 150 Bq m-3 because waterborne 222Rn concentrations also are low (80 kBq m-3). This

  6. National survey on the natural radioactivity and 222Rn exhalation rate of building materials in The Netherlands.

    PubMed

    de Jong, P; van Dijk, W; van der Graaf, E R; de Groot, T J H

    2006-09-01

    The present study reports on results of a nation-wide survey on the natural radioactivity concentrations and Rn exhalation rates of the prevailing building materials in the Netherlands. In total 100 samples were taken and analyzed for the activity concentrations of Ra, Ra, Th, and K and for their Rn exhalation rate. The sampled materials consisted of gypsum products, aerated concrete, sand-lime and clay bricks, mortars and concrete, representing about 95% of the stony building materials used in the construction of Dutch homes. The laboratory analyses were performed according to two well-documented standard procedures, the interlaboratory reproducibility of which is found to be within 5% on average. The highest radionuclide concentrations were found in a porous inner wall brick to which fly ash was added. The second highest were clay bricks with average Ra and Ra levels around 40 Bq kg. Concrete and mortar show the highest exhalation rates with a fairly broad range of 1 to 13 microBq (kg s). Low natural radioactivity levels are associated with either natural gypsum (products) or gypsum from flue gas desulphurization units, and low exhalation rates with clay bricks. To evaluate the radiological impact the radioactivity concentrations in each sample were combined into a so-called dose factor, representing the absorbed dose rate in a room with a floor, walls and ceiling of 20 cm of the material in question. For that purpose, calculations with the computer codes MCNP, Marmer and MicroShield on the specific absorbed dose rates were incorporated in the paper. The results of these codes corresponded within 6% and average values were calculated at 0.90, 1.10, and 0.080 nGy h per Bq kg for the U series, the Th series, and K, respectively. Model calculations on the external dose rate, based on the incidence of the various building materials in 1,336 living rooms, are in accordance with measured data.

  7. Relationships between 222Rn dissolved in ground water supplies and indoor 222Rn concentrations in some Colorado front range houses

    USGS Publications Warehouse

    Folger, P.F.; Nyberg, P.; Wanty, R.B.; Poeter, E.

    1994-01-01

    Indoor 222Rn concentrations were measured in 37 houses with alpha track detectors placed in water-use rooms near water sources (bathrooms, laundry rooms, and kitchens) and in non-water-use living rooms, dining rooms, and bedrooms away from water sources. Results show that relative contributions of 222Rn to indoor air from water use are insignificant when soil-gas concentrations are high but become increasingly important as the ratio of 222Rn-in-water:222Rn-in-soil gas increases. High soil-gas 222Rn concentrations may mask 222Rn contributions from water even when waterborne 222Rn concentrations are as high as 750 kBq m-3. Ground water in Precambrian Pikes Peak granite averages 340 kBq m-3222Rn, vs. 170 kBq m-3 in Precambrian migmatite, but average 222Rn concentrations in soil gas are also lower in migmatite. Because the ratio of 222Rn-in- water:222Rn-in-soil gas may be consistently higher for houses in migmatite than in Pikes Peak granite, indoor air in houses built on migmatite may have a greater relative contribution from water use even though average 222Rn concentrations in the water are lower. Continuous monitoring of 222Rn concentrations in air on 15-min intervals also indicates that additions to indoor concentrations from water use are significant and measurable only when soil-gas concentrations are low and concentrations in water are high. When soil-gas concentrations were mitigated to less than 150 Bq m-3 in one house, water contributes 20-40% of the annual indoor 222Rn concentration in the laundry room (222Rn concentration in water of 670 kBq m-3). Conversely, when the mitigation system is inactive, diurnal fluctuations and other variations in the soil-gas 222Rn contribution swamp the variability due to water use in the house. Measurable variations in indoor concentrations from water use were not detected in one house despite a low soil-gas contribution of approximately 150 Bq m-3 because waterborne 222Rn concentrations also are low (80 kBq m-3). This

  8. 222Rn concentrations in greenhouses in Aomori Prefecture, Japan.

    PubMed

    Iyogi, T; Hisamatsu, S; Inaba, J

    2006-02-01

    Greenhouses are possible places with high 222Rn concentrations, since soil, the source of 222Rn, is directly exposed inside them. To examine this point, 222Rn concentrations in 28 greenhouses at five locations in Aomori Prefecture were measured for approximately 1 year with passive Rn detectors. For 1 week, measurements of 222Rn concentration and working level were also carried out with active detectors to get equilibrium factors and the ratio of 222Rn concentration in working time to non-working time in selected greenhouses. The geometric mean of annual 222Rn concentrations in greenhouses was 13 Bq m-3, and the same as that in dwellings and lower than that in indoor workplaces in the prefecture. However, variation of the 222Rn concentrations was far larger than in other environments, and ranged from the lowest level in outdoor workplaces to the highest level in indoor workplaces. Significant seasonal variation was also observed in 222Rn concentrations. The mean effective dose from 222Rn and its progenies was estimated to be 0.047 mSv year-1 for a farmer working in a greenhouse.

  9. Inferring 222Rn soil fluxes from ambient 222Rn activity and eddy covariance measurements of CO2

    NASA Astrophysics Data System (ADS)

    van der Laan, Sander; Manohar, Swagath; Vermeulen, Alex; Bosveld, Fred; Meijer, Harro; Manning, Andrew; van der Molen, Michiel; van der Laan-Luijkx, Ingrid

    2016-11-01

    We present a new methodology, which we call Single Pair of Observations Technique with Eddy Covariance (SPOT-EC), to estimate regional-scale surface fluxes of 222Rn from tower-based observations of 222Rn activity concentration, CO2 mole fractions and direct CO2 flux measurements from eddy covariance. For specific events, the regional (222Rn) surface flux is calculated from short-term changes in ambient (222Rn) activity concentration scaled by the ratio of the mean CO2 surface flux for the specific event to the change in its observed mole fraction. The resulting 222Rn surface emissions are integrated in time (between the moment of observation and the last prior background levels) and space (i.e. over the footprint of the observations). The measurement uncertainty obtained is about ±15 % for diurnal events and about ±10 % for longer-term (e.g. seasonal or annual) means. The method does not provide continuous observations, but reliable daily averages can be obtained. We applied our method to in situ observations from two sites in the Netherlands: Cabauw station (CBW) and Lutjewad station (LUT). For LUT, which is an intensive agricultural site, we estimated a mean 222Rn surface flux of (0.29 ± 0.02) atoms cm-2 s-1 with values > 0.5 atoms cm-2 s-1 to the south and south-east. For CBW we estimated a mean 222Rn surface flux of (0.63 ± 0.04) atoms cm-2 s-1. The highest values were observed to the south-west, where the soil type is mainly river clay. For both stations good agreement was found between our results and those from measurements with soil chambers and two recently published 222Rn soil flux maps for Europe. At both sites, large spatial and temporal variability of 222Rn surface fluxes were observed which would be impractical to measure with a soil chamber. SPOT-EC, therefore, offers an important new tool for estimating regional-scale 222Rn surface fluxes. Practical applications furthermore include calibration of process-based 222Rn soil flux models, validation

  10. Radon (222Rn) level variations on a regional scale: influence of the basement trace element (U, Th) geochemistry on radon exhalation rates.

    PubMed

    Ielsch, G; Thiéblemont, D; Labed, V; Richon, P; Tymen, G; Ferry, C; Robé, M C; Baubron, J C; Béchennec, F

    2001-01-01

    The approach proposed in this study provides insight into the influence of the basement geochemistry on the spatial distribution of radon (222Rn) levels both at the soil/atmosphere interface and in the atmosphere. We combine different types of in situ radon measurements and a geochemical classification of the lithologies, based on 1/50,000 geological maps, and on their trace element (U, Th) contents. The advantages of this approach are validated by a survey of a stable basement area of Hercynian age, located in South Brittany (western France) and characterized by metamorphic rocks and granitoids displaying a wide range of uranium contents. The radon source-term of the lithologies, their uranium content, is most likely to be the primary parameter which controls the radon concentrations in the outdoor environment. Indeed, the highest radon levels (> or = 100 Bq m-3 in the atmosphere, > or = 100 mBq m-2 s-1 at the surface of the soil) are mostly observed on lithologies whose mean uranium content can exceed 8 ppm and which correspond to peraluminous leucogranites or metagranitoids derived from uraniferous granitoids.

  11. Determination of (222)Rn absorption properties of polycarbonate foils by liquid scintillation counting. Application to (222)Rn measurements.

    PubMed

    Mitev, K; Cassette, P; Georgiev, S; Dimitrova, I; Sabot, B; Boshkova, T; Tartès, I; Pressyanov, D

    2016-03-01

    This work demonstrates that a Liquid Scintillation Counting (LSC) technique using a Triple to Double Coincidence Ratio counter with extending dead-time is very appropriate for the accurate measurement of (222)Rn activity absorbed in thin polycarbonate foils. It is demonstrated that using a toluene-based LS cocktail, which dissolves polycarbonates, the (222)Rn activity absorbed in thin Makrofol N foil can be determined with a relative standard uncertainty of about 0.7%. A LSC-based application of the methodology for determination of the diffusion length of (222)Rn in thin polycarbonate foils is proposed and the diffusion length of (222)Rn in Makrofol N (38.9±1.3µm) and the partition coefficient of (222)Rn in Makrofol N from air (112±12, at 20°C) and from water (272±17, at 21°C) are determined. Calibration of commercial LS spectrometers for (222)Rn measurements by LSC of thin polycarbonate foils is performed and the minimum detectable activities by this technique are estimated.

  12. Internal exposure from building materials exhaling (222)Rn and (220)Rn as compared to external exposure due to their natural radioactivity content.

    PubMed

    Ujić, Predrag; Celiković, Igor; Kandić, Aleksandar; Vukanac, Ivana; Durasević, Mirjana; Dragosavac, Dusan; Zunić, Zora S

    2010-01-01

    The main scope of this paper is to point out the importance of introducing radon and thoron exhalation measurements from building materials in the regulating frame. Currently (2009), such a regulation of this kind of exposure is not explicitly included in the Serbian regulating network. To this end, this work reports concentration measurements of (226)Ra, (232)Th and (40)K and radon and thoron exhalation rates from building materials used in Serbia. Following detailed analysis, it was noticed that both internal exposures to radon and/or thoron exhaling from building materials may exceed external exposures to their precursors contained therein.

  13. Occurrence of 222Rn, 226Ra, 228Ra and U in groundwater in Fujian Province, China.

    PubMed

    Zhuo, W; Iida, T; Yang, X

    2001-01-01

    222Rn, 226Ra, 228Ra and U were determined in a total of 552 groundwater samples collected throughout Fujian Province of China. The geometric mean concentrations of 222Rn, 226Ra, 228Ra and total U in the groundwater were 147.8 kBq m-3, 12.7 Bq m-3, 30.2 Bq m-3 and 0.54 microgram kg-1, respectively. High groundwater 222Rn was explained by the predominantly granitic rock aquifers in Fujian. A lifetime risk of 1.7 x 10(-3) was estimated for the ingestion of groundwater 222Rn. High ratios of 228Ra to 226Ra contents (geometric mean of 2.4) and their disproportion suggest that 228Ra should also be measured in the assessment of population doses from drinking water in the regions of high rock or soil 232Th. No significant correlation between the 222Rn concentrations in groundwater and air was found.

  14. Radon ((222)Rn) concentration in indoor air near the coal mining area of Nui Beo, North of Vietnam.

    PubMed

    Nhan, Dang Duc; Fernando, Carvalho P; Thu Ha, Nguyen Thi; Long, Nguyen Quang; Thuan, Dao Dinh; Fonseca, Heloisa

    2012-08-01

    Concentrations of radioactive radon gas ((222)Rn) were measured using passive monitors based on LR115 solid state track detectors during June-July 2010 in indoor air of dwellings in the Nui Beo coal mining area, mostly in Cam Pha and Ha Long coastal towns, Quang Ninh province, in the North of Vietnam. Global results of (222)Rn concentrations indoors varied from ≤6 to 145 Bq m(-3) averaging 46 ± 26 Bq m(-3) (n = 37), with a median value of 47 Bq m(-3). This was similar to outdoor (222)Rn concentrations in the region, averaging 43 ± 19 Bq m(-3) (n = 10), with a median value of 44 Bq m(-3). Indoor (222)Rn concentrations in the coastal town dwellings only were in average lower although not significantly different from indoor (222)Rn concentrations measured at the coal storage field near the harbor, 67 ± 4 Bq m(-3) (n = 3). Furthermore, there was no significant difference in the average (222)Rn concentration in indoor air measured in the coastal towns region and those at the touristic Tuan Chau Island located about 45 km south of the coal mine, in the Ha Long Bay. The indoor (222)Rn concentration in a floating house at the Bai Tu Long Bay, and assumed as the best estimate of the baseline (222)Rn in surface air, was 27 ± 3 Bq m(-3) (n = 3). Indoor average concentration of (222)Rn in dwellings at the Ha Noi city, inland and outside the coal mining area, was determined at 30 Bq m(-3). These results suggest that (222)Rn exhalation from the ground at the Nui Beo coal mining area may have contributed to generally increase (222)Rn concentration in the surface air of that region up to 1.7 times above the baseline value measured at the Bai Tu Long Bay and Ha Noi. The average indoor concentration of (222)Rn in Cam Pha-Ha Long area is about one-third of the value of the so-called Action Level set up by the US EPA of 148 Bq m(-3). Results suggest that there is no significant public health risk from (222)Rn exposure in the study region.

  15. 222Rn variations in Mystery Cave, Minnesota

    USGS Publications Warehouse

    Lively, R.S.; Krafthefer, B.C.

    1995-01-01

    222Rn concentrations and meteorological parameters were measured at 4- h intervals over a 2-y period in Mystery Cave, southeastern Minnesota. Continuous radon monitors and meteorological sensors connected to data loggers were installed at several locations along commercial tour routes. 222Rn concentrations ranged as high as 25 kBq m-3 in summer and 20 kBq m-3 in winter. Average winter concentrations were lower than summer by at least a factor of two. Seasonal radon variations were correlative with outside air temperatures. During the winter, radon concentrations were observed to fluctuate periodically by factors of 20 or more in under 24 h. Both the long- and short-term variations are correlative with temperature- induced mixing of cave air with surface air.

  16. 222Rn variations in Mystery Cave, Minnesota.

    PubMed

    Lively, R S; Krafthefer, B C

    1995-04-01

    222Rn concentrations and meteorological parameters were measured at 4-h intervals over a 2-y period in Mystery Cave, southeastern Minnesota. Continuous radon monitors and meteorological sensors connected to data loggers were installed at several locations along commercial tour routes. 222Rn concentrations ranged as high as 25 kBq m-3 in summer and 20 kBq m-3 in winter. Average winter concentrations were lower than summer by at least a factor of two. Seasonal radon variations were correlative with outside air temperatures. During the winter, radon concentrations were observed to fluctuate periodically by factors of 20 or more in under 24 h. Both the long- and short-term variations are correlative with temperature-induced mixing of cave air with surface air.

  17. Soil gas 222Rn and volcanic activity at El Hierro (Canary Islands) before and after the 2011 submarine eruption

    NASA Astrophysics Data System (ADS)

    Padilla, G.; Hernández, P. A.; Padrón, E.; Barrancos, J.; Melián, G.; Dionis, S.; Rodríguez, F.; Nolasco, D.; Calvo, D.; Hernández, I.; Pereza, M. D.; Pérez, N. M.

    2012-04-01

    anomalous soil gas 222Rn activities were mainly detected along the major volcano-structural features of the island. The time series recorded at HIE02 and HIE03 showed clear 222Rn precursory signatures of the volcanic eruption. Observed 222Rn activity ranged from negligible values to 16.5 and 1.6 kBqm-3 at HIE02 and HIE03 stations, respectively. Individual 222Rn peaks registered in both stations had been also very useful to forecast later pulses on the volcanic activity. In addition, 222Rn/220Rn ratios in both stations showed a strong increase prior the eruption.

  18. Errors in measurements of 222Rn in methane and carbon dioxide using scintillation cells calibrated for 222Rn in air.

    PubMed

    Jenkins, Phillip H; Burkhart, James F; Camley, Robert E

    2014-03-01

    Scintillation cells are used typically for measuring the concentration of (222)Rn in air and are calibrated for that purpose. However, scintillation cells are sometimes used for measuring (222)Rn in natural gas or carbon dioxide. The counting efficiencies of scintillation cells for measurements of (222)Rn in these gases should be different from those for measuring (222)Rn in air because the ranges of alpha particles emitted by (222)Rn and its progeny are greater in methane and smaller in carbon dioxide than in air. If these effects are not taken into consideration, measurements of (222)Rn in natural gas will be biased high and in carbon dioxide will be biased low. The authors previously investigated the effects of barometric pressure on measurements of (222)Rn in air using scintillation cells. A modeling technique was used in a previous study to calculate theoretical errors that would result if atmospheric pressure were not considered. In the current study, the same modeling technique was used to calculate theoretical errors that would be made for measurements of (222)Rn in methane and carbon dioxide if the calibration for (222)Rn in air were used. Results are presented for four types of scintillation cells of varying geometries and for barometric pressures representative of four elevations ranging from sea level to 1,963 m (6,440 feet). These results indicate that the errors introduced by the ranges of the alpha particles in gases different from air can be significant. Depending on the type of cell and the local pressure, a measurement of (222)Rn in methane may be biased high by 2-7%, while a measurement of (222)Rn in CO2 may be biased low by 15-20% if the calibration for (222)Rn in air is used.

  19. A method for emanation coefficient measurements of 222Rn and 220Rn from soils

    NASA Astrophysics Data System (ADS)

    De Martino, S.; Sabbarese, C.

    A new method to determine emanation coefficient of 222Rn and 220Rn from soil samples is presented. The aim of the present work is to obtain a useful, rapid and noise free method to make soil sample measurements. The method is based on the measurements of specific activities of 220Rn and 222Rn in a sealed chamber using α-spectrometry and on the measurements of specific activities of 232Th and 226Ra using γ-spectrometry. The specific activities of radon isotopes are measured using the electrostatic collection of polonium isotopes on the silicon surface barrier detector mounted at the top of a chamber containing the soil sample. In the chamber volume, the process of balance has been studied and the results show that the time needed to achieve the equilibrium is shorter than in the presence of free exhalation.

  20. Analysis of recharge by paddy field irrigation using 222Rn concentration in groundwater as an indicator

    NASA Astrophysics Data System (ADS)

    Hamada, Hiromasa; Komae, Takami

    1998-02-01

    Groundwater recharge must be well understood in order that water resources can be effectively used and contamination of groundwater by surface water can be prevented. Evaluating recharge from groundwater levels alone does not show downward flow when outflow exceeds recharge. This article showed the variation of 222Rn concentrations in soil water according to degree of saturation in the aquifer. The theory used for analysis is based on gas solubility theory between two phases, liquid and gas. Field investigation confirmed that 222Rn concentration in the groundwater at the surface of a saturated zone decreases with downward flow in the unsaturated zone above. After that, we investigated the recharge by paddy fields with the method using 222Rn concentration in the groundwater at the surface of a saturated zone. The results showed that the state of recharge could be analyzed as expected, i.e., the occurrence of downward flow of soil water pushed out by irrigation water, unsaturated percolation during the irrigation period, and the redistribution of soil water after the release of ponding water. The degree of saturation of downward flow in the unsaturated zone was calculated to be about 50% from the ratio of 222Rn concentration in the irrigation period to that in the non-irrigation period. This shows that the downward flow in the underlying layer was very unsaturated. When the groundwater table is deep, and less pervious soil overlies more pervious soil, it is known that percolation from paddy fields is unsaturated in the underlying layer. Since the saturated hydraulic conductivity of the underlying layer was on the order of 10 -1 cm/s and that of surface soil is 10 -5 to 10 -6 cm/s, it is likely that unsaturated downward flow occurred. The 222Rn concentration in the groundwater at the surface of a saturated zone is a useful indicator for detecting the existence of downward flow to the saturated zone through an unsaturated aquifer.

  1. Determination of waterborne {sup 222}Rn concentrations using AC canisters

    SciTech Connect

    Mancini, C.; Giannelli, G.

    1995-09-01

    A method for measuring {sup 222}Rn concentration in water using charcoal canisters is presented. {sup 222}Rn is transferred within a few minutes from water contained in a 0.720 L bottle to a charcoal canister using a portable degassing unit. In the laboratory, gamma counting is performed at least 10 h after sampling to determine waterborne {sup 222}Rn concentration. The results obtained with charcoal canisters are compared to measurements made with Marinelli beakers calibrated in a comparison with liquid scintillation counting. The efficiency of transferring dissolved {sup 222}Rn in water to activated charcoal is 99% based on measurements made using Marinelli beakers. The lower limit of detection at the 95% confidence level is approximately 1 kBq m{sup -3} for a 15 min gamma count. the system was used to measure radon concentration in mineral groundwater near Rome. 7 refs., 1 fig., 1 tab.

  2. Contribution of 222Rn in domestic water supplies to 222Rn in indoor air in Colorado homes

    USGS Publications Warehouse

    Lawrence, E.P.; Wanty, R.B.; Nyberg, P.

    1992-01-01

    The contribution of 222Rn from domestic water wells to indoor air was investigated in a study of 28 houses near Conifer, CO. Air concentrations determined by alpha-track detectors (ATDs) and continuous radon monitors were compared with the predictions of a single-cell model. In many of the houses, the water supply was shown to contribute significantly to levels of indoor 222Rn. The data from the ATD study were augmented with a continuous monitoring study of a house near Lyons, CO. The well water in that house has the highest known concentration of 222Rn in water yet reported (93 MBq m-3). The temporal pattern in the indoor 222Rn concentration corresponds to water-use records. In general, it is difficult to quantify the proportion of indoor radon attributable to water use. Several lines of evidence suggest that the single-cell model underestimates this proportion. Continuous- monitoring data, although useful, are impractical due to the cost of the equipment. We propose a protocol for 222Rn measurement based on three simultaneous integrating radon detectors that may help estimate the proportion of indoor 222Rn derived from the water supply.

  3. The Effect of CO2 on the Measurement of 220Rn and 222Rn with Instruments Utilising Electrostatic Precipitation

    DOE PAGES

    Lane-Smith, Derek; Sims, Kenneth

    2013-06-09

    In some volcanic systems, thoron and radon activity and CO2 flux, in soil and fumaroles, show a relationship between (220Rn/222Rn) and CO2 efflux. It is theorized that deep, magmatic sources of gas are characterized by high 222Rn activity and high CO2 efflux, whereas shallow sources are indicated by high 220Rn activity and relatively low CO2 efflux. In this paper we evaluate whether the observed inverse relationship is a true geochemical signal, or potentially an analytical artifact of high CO2 concentrations. We report results from a laboratory experiment using the RAD7 radon detector, known 222Rn (radon) and 220Rn (thorn), and amore » controllable percentage of CO2 in the carrier gas. Our results show that for every percentage of CO2, the 220Rn reading should be multiplied by 1.019, the 222Rn radon should be multiplied by 1.003 and the 220Rn/222Rn ratio should be multiplied by 1.016 to correct for the presence of the CO2.« less

  4. European 222Rn inventory for applied atmospheric studies

    NASA Astrophysics Data System (ADS)

    Szegvary, T.; Conen, F.; Ciais, P.

    The radioactive noble gas 222Rn, naturally emitted from land surfaces, is widely used as a tracer in characterising atmospheric transport and mixing processes. A constant and homogenous 222Rn source of 1 atom cm -2 s -1 is generally assumed, sometimes less in northern latitudes. It is well known that 222Rn flux varies in space and time but a robust description of it on a continental scale has not been possible before. Here, we present for the first time a spatially and temporally resolved 222Rn source map for the European Continent (European Union, Norway, former Yugoslavia and Switzerland). It is based on the correlation between the 222Rn flux and terrestrial γ-dose rate. Total γ-dose rate is monitored in this area at nearly 3600 stations continuously and the terrestrial component can be extracted from these measurements. On a resulting 0.5° × 0.5° map, mean annual values of 222Rn flux ranged from 0.03 to 1.76 atom cm -2 s -1, half of the values being between 0.40 and 0.70 atom cm -2 s -1. The source strength was patchy but exhibited a decreasing trend with increasing latitude. Large values were mainly found on the Iberian Peninsula, small values along coasts and in northern and eastern parts of Europe. The seasonal amplitude in 222Rn flux south of 55°N was small in 2006 with weekly averages deviating less than ±15% from the annual mean. Between 65°N and 70°N, weekly means are 2.5 times larger in summer than in winter.

  5. A Novel Application for 222Rn Emanation Standards

    PubMed Central

    Laureano-Perez, L.; Collé, R.; Jacobson, D.R.; Fitzgerald, R.; Khan, N.S.; Dmochowski, I.J.

    2013-01-01

    In collaboration with the University of Pennsylvania, a 222Rn emanation source was used for the determination of the binding affinity of radon to a cryptophane molecular host. This source was similar to a 222Rn emanation standard that was developed and disseminated by the National Institute of Standards and Technology (NIST). The novel experimental design involved performing the reactions at femtomole levels, developing exacting gravimetric sampling methods and making precise 222Rn assays by liquid scintillation counting. A cryptophane-radon association constant was determined, KA = (49,000 ± 12,000) L· mol−1 at 293 K, which was the first measurement of radon binding to a molecular host. PMID:22455833

  6. Behaviour of {sup 222}Rn at cryogenic temperatures

    SciTech Connect

    Lindemann, Sebastian; Simgen, Hardy; Zuzel, Grzegorz

    2011-04-27

    The behaviour of radon in a cryogenic environment is still not well known. Therefore, measured radon emanation rates at room temperature cannot be translated directly to cryogenic conditions. In this work we present a table-top experiment that provides a direct way of determining the behaviour of {sup 222}Rn in cryogenic argon and helium at liquid argon temperature. We observe an increased emanation rate of {sup 222}Rn atoms to liquid argon compared to the rate observed to helium at room temperature. We also find that {sup 222}Rn atoms stick to cold metal surfaces when emanated to helium at liquid argon temperature but partly distribute in the liquid when emanated to cryogenic argon. Concluding, we give possible interpretations of the observations.

  7. Highly Sensitive Measurements of 222Rn Diffusion and Emanation

    SciTech Connect

    Zuzel, Grzegorz

    2005-09-08

    Highly sensitive techniques for determination of the 222Rn emanation from solids and diffusion through different membranes are presented. 222Rn and its daughters are measured via the alpha decays in special proportional counters at the absolute sensitivity of {approx}30 {mu}Bq. Radon diffusion can be measured at the level of {approx}10-13 cm2/s. Several samples were examined, e.g. stainless steel, teflon, various gaskets (emanation and diffusion measurements) and tanks. A combination of measurements of the 222Rn diffusion and emanation of thin nylon foils (used in the Borexino experiment) allowed the determination of 226Ra in the materials of interest at the level of {approx}10-12 g/g 238U-equivalent.

  8. Variation of 222Rn in public drinking water supplies.

    PubMed

    Drane, W K; York, E L; Hightower, J H; Watson, J E

    1997-12-01

    The U.S. Environmental Protection Agency has proposed regulating 222Rn in public drinking water. When implemented, the regulation will require periodic sampling to demonstrate compliance. The work reported in this paper was conducted to evaluate how reliably grab samples can be used to characterize the average 222Rn concentration in a groundwater source. Periodic samples were collected from 14 wells over sampling periods ranging from 2 to 26 mo. Samples were collected using a "slow-flow" collection method, and samples were analyzed using liquid scintillation techniques. The results reveal variation in 222Rn concentration over the study period; however, for the 1,468 samples collected from the 14 wells, approximately 97% of the measurement results were within 30% of the mean value for the well.

  9. A micromegas detector for {sup 222}Rn emanations measurements

    SciTech Connect

    García, J. A.; Garza, J. G.; Irastorza, I. G.; Mirallas, H.

    2013-08-08

    The {sup 222}Rn emanation has significant contribution in the overall background for rare event searches experiments. In order to measure this emanations a high sensitivity detector has been designed. The detection method is based on the electrostatic collection of the {sup 222}Rn daughters on a Micromegas detector. Using a chamber with a volume of 21.2 l for the collection of {sup 218}Po and {sup 214}Po progeny of {sup 222}Rn and a 12 × 12cm{sup 2} pixelized Micromegas for the α detection. The advantages of the Micromegas detectors are the low intrinsic radioactivity and the track reconstruction of the α’s, having excellent capabilities for event discrimination.

  10. Measurements of radon exhalation rate in NORM used as consumer products in Japan.

    PubMed

    Iwaoka, Kazuki; Hosoda, Masahiro; Yajima, Kazuaki; Tokonami, Shinji

    2017-01-25

    Twenty-five beauty products known to contain natural radionuclides were collected, and their (222)Rn mass exhalation rates were measured. The effective doses to workers due to (222)Rn exhaled from these products were estimated. The (222)Rn mass exhalation rates of these products were below 177 μBq kg(-1) s(-1) and were almost identical to those of natural rocks in Japan. The maximum effective dose of (222)Rn exhaled from these products was 71 μSv y(-1).

  11. 222Rn and 220Rn diffusion in two mediums

    NASA Astrophysics Data System (ADS)

    Markovic, V. M.; Nikezic, D.; Stevanovic, N.

    2017-06-01

    In this paper diffusion of radon isotopes 222Rn and 220Rn is considered in diffusion chamber which is covered with radon soluble membrane. Diffusion is considered in two mediums, membrane and air inside of diffusion chamber. Analytical and numerical solutions are presented and time dependence of total activity inside of chamber is determined. Presented analytical solution can be of use for determining time for which equilibrium state can be reach in diffusion chamber. It is shown that thickness of membrane can strongly influence on radon concentration inside of chamber, especially for 220Rn isotope. Detectors for 222Rn measurements which discriminate 220Rn isotope can be devised by simply increasing of membrane thickness. For plain filter paper of 1 cm thickness inside of chamber, there will be 0.5% of outside 220Rn concentration, while 222Rn concentration will be reduced on 50%. In this way, by placing two chambers with thin and thick membrane, concentrations of both 222Rn and 220Rn can be easily determined.

  12. Risk analysis of 222Rn gas received from East Anatolian Fault Zone in Turkey

    NASA Astrophysics Data System (ADS)

    Yilmaz, Mucahit; Kulahci, Fatih

    2016-06-01

    In this study, risk analysis and probability distribution methodologies are applied for 222Rn gas data received from Sürgü (Malatya) station located on East Anatolian Fault Zone (EAFZ). 222Rn data are recorded between 21.02.2007 and 06.06.2010 dates. For study are used total 1151 222Rn data. Changes in concentration of 222Rn are modeled as statistically.

  13. 222Rn emanation measurements at extremely low activities

    PubMed

    Rau; Heusser

    2000-07-01

    For the solar neutrino experiment Borexino, a system has been set up to measure emanation of 222Rn in samples of up to 80 litres volume. The apparatus has been constructed to high vacuum standard and consists mainly of parts made from electropolished stainless steel. The low blank activity of the system together with a highly sensitive detection method for the extracted Rn leads to a sensitivity level in the range 70-100 microBq 222Rn. Due to the large sample capacity of the emanation chambers, it is possible to measure specific emanation rates as low as several microBq/m2. Some measurements characterizing the performance of the apparatus are discussed.

  14. Integrated measurements of 222Rn by absorption in Makrofol

    NASA Astrophysics Data System (ADS)

    Pressyanov, Dobromir; Buysse, Jozef; Poffijn, André; Van Deynse, Annick; Meesen, Geert

    2004-01-01

    Recently, a method for long-term 222Rn measurements based on the radon absorption ability and track-etch properties of Makrofol has been proposed. The basic idea is to remove, after exposure, a surface layer, thicker than the range of the α-particles of the 222Rn or 220Rn progenies, and to study the track density of the electrochemically etched tracks at that depth. This paper summarizes the performance of the method under laboratory and field conditions. The effects on the response due to differences in pressure, temperature, humidity, the presence of 220Rn, dust and cigarette smoke in the air have been studied experimentally. The effect of these factors, but the temperature, is either absent, or restricted to about 10% for the very extreme cases. The variation of the response at the studied depth of 83 μm over the temperature interval 15-25°C is ±12% around the 19.5°C value. The field comparison conducted showed an agreement between the method of radon absorption in Makrofol and the conventional diffusion chambers. Therefore, a potential for long-term 222Rn measurements in the human environment by radon absorption in Makrofol or equivalent polycarbonates clearly exists.

  15. Analysis of ground-based 222Rn measurements over Spain: Filling the gap in southwestern Europe

    NASA Astrophysics Data System (ADS)

    Grossi, C.; Àgueda, A.; Vogel, F. R.; Vargas, A.; Zimnoch, M.; Wach, P.; Martín, J. E.; López-Coto, I.; Bolívar, J. P.; Morguí, J. A.; Rodó, X.

    2016-09-01

    Harmonized atmospheric 222Rn observations are required by the scientific community: these data have been lacking in southern Europe. We report on three recently established ground-based atmospheric 222Rn monitoring stations in Spain. We characterize the variability of atmospheric 222Rn concentrations at each of these stations in relation to source strengths, local, and regional atmospheric processes. For the study, measured atmospheric 222Rn concentrations, estimated 222Rn fluxes, and regional footprint analysis have been used. In addition, the atmospheric radon monitor operating at each station has been compared to a 222Rn progeny monitor. Annual means of 222Rn concentrations at Gredos (GIC3), Delta de l'Ebre (DEC3), and Huelva (UHU) stations were 17.3 ± 2.0 Bq m-3, 5.8 ± 0.8 Bq m-3, and 5.1 ± 0.7 Bq m-3, respectively. The GIC3 station showed high 222Rn concentration differences during the day and by seasons. The coastal station DEC3 presented background concentrations typical of the region, except when inland 222Rn-rich air masses are transported into the deltaic area. The highest 222Rn concentrations at UHU station were observed when local recirculation facilitates accumulation of 222Rn from nearby source represented by phosphogypsum piles. Results of the comparison performed between monitors revealed that the performance of the direct radon monitor is not affected by meteorological conditions, whereas the 222Rn progeny monitor seems to underestimate 222Rn concentrations under saturated atmospheric conditions. Initial findings indicate that the monitor responses seem to be in agreement for unsaturated atmospheric conditions but a further long-term comparison study will be needed to confirm this result.

  16. Estimation of 222Rn release from the phosphogypsum board used in housing panels.

    PubMed

    Jang, Mee; Kang, Chang-Sun; Hyun Moon, Joo

    2005-01-01

    Phosphogypsum board is a popular construction material used for housing panels in Korea. Phosphogypsum often contains (226)Ra which decays into (222)Rn through an alpha transformation. (222)Rn emanated from the (226)Ra-bearing phosphogypsum board has drawn the public concern due to its potential radiological impacts to indoor occupants. The emanation rate of (222)Rn from the board is estimated in this paper. A mathematical model of the emanation rate of (222)Rn from the board is presented and validated through a series of experiments. The back diffusion effect due to accumulation of (222)Rn-laden air was incorporated in the model and found to have a strong impact on the (222)Rn emanation characteristics.

  17. Apparatus for the Measurement of {sup 222}Rn Diffusion

    SciTech Connect

    Mamedov, F.; Konicek, J.; Stekl, I.

    2009-11-09

    A new apparatus for the measurement of {sup 222}Rn diffusion through shielding foils developed in the frame of the NEMO collaboration is briefly described. The setup is based on the electrostatic collection of radon progenies {sup 218}Po and {sup 214}Po. The NEMO project is an underground experiment for the study of double beta decay processes. For such type of experiments the efficient suppression of background caused by radon is essential. The first test of the apparatus has been carried out using Penefol foil (0.8 mm thickness) and the suppression factor of radon concentration has been obtained.

  18. sup 222 Rn, sup 222 Rn progeny and sup 220 Rn progeny as atmospheric tracers of air masses at the Mauno Loa Observatory

    SciTech Connect

    Hutter, A.R.; George, A.C.; Maiello, M.L.; Fisenne, I.M.; Larsen, R.J.; Beck, H.L.; Wilson, F.C.

    1990-03-01

    {sup 222}Rn, {sup 222}Rn progeny and {sup 220}Rn progeny concentrations in air were measured at the Mauna Loa Observatory (MLO) in Hawaii during March 1989 in order to investigate the feasibility of using them as atmospheric tracers to help determine local air mass flow patterns. Charcoal traps, cooled to dry ice temperatures, were used to collect {sup 222}Rn, which was subsequently measured in pulse ionization chambers at the Environmental Measurements Laboratory (EML). {sup 222}Rn progeny and {sup 220}Rn progeny for 37 samples were measured at the Observatory by sampling high volumes of air through filters, which were counted for up to 11 h in alpha scintillation counters. Individual progeny concentrations were calculated using both least squares and maximum likelihood techniques. In general, {sup 222}Rn progeny and {sup 220}Rn progeny concentrations were low when free tropospheric air was present (downslope and tradewind conditions), and consistently higher when surface air from the island broke through the trade wind inversion layer (upslope conditions). The data suggest that {sup 222}Rn, {sup 222}Rn progeny, or {sup 220}Rn progeny monitoring may provide new and useful information to help indicate the different air flow patterns present at MLO. 17 refs., 5 figs., 2 tabs.

  19. Quantitative goals for a 222Rn multimedia mitigation plan.

    PubMed

    Newton, B M; Watson, J E; Cote, R A

    2001-11-01

    The U.S. Environmental Protection Agency's revised proposed 222Rn in drinking water regulation gives states or individual community water systems the option of compliance with the maximum contaminant level or compliance with the higher, alternate maximum contaminant level accompanied by the implementation of a multimedia mitigation plan. If states or water suppliers choose to comply with the alternate maximum contaminant level, the health risk reduction achieved by multimedia mitigation programs must be equal to or greater than the health risk reduction that would be achieved by compliance with the maximum contaminant level rather than the alternate maximum contaminant level. We have developed a method to determine quantitative goals for mitigating existing homes and building new 222Rn-resistant homes to achieve a health risk reduction to the public equivalent to the health risk differential between alternate maximum contaminant level and maximum contaminant level compliance. This method can be applied to an entire state, a portion of a state, or to an individual water supplier. The method was applied to North Carolina, and it was concluded that, over time, the health risk reduction achievable from alternate maximum contaminant level compliance and the implementation of a multimedia mitigation program would be much greater than from compliance with the maximum contaminant level.

  20. Distribution patterns of salinity and 222Rn in Yatsushiro Inland Sea, Kyushu, Japan

    NASA Astrophysics Data System (ADS)

    Nikpeyman, Y.; Ono, N.; Hosono, T.; Yang, H.; Ichiyanagi, K.; Shimada, J.; Takikawa, K.

    2015-03-01

    Submarine Groundwater Discharge (SGD), as a way through which solutes and nutrients travel from terrestrial areas towards coastal areas, is part of the hydrological cycle. Various methods are used to locate SGD at different scales. Among them, 222Rn has been developed with the viewpoint of accurate local estimations of SGD points indirectly. This research aims to identify SGD areas in the Yatsushiro Sea, southwest Japan, using the 222Rn method, while considering rivers with high 222Rn concentration in the study area. The area is an inland sea with high tidal fluctuations and there is a large contribution between the sea and groundwater, which are greatly affected by rivers. A multi-detector 222Rn survey has been carried out simultaneously with sea water electrical conductivity (EC) and temperature. In addition, several river grab samples were analysed for 222Rn concentration. Considering the sea water radon distribution and river characteristics, several points were selected for future SGD volume estimations.

  1. Removal of 222Rn daughters from metal surfaces

    NASA Astrophysics Data System (ADS)

    Zuzel, G.; Wojcik, M.; Majorovits, B.; Lampert, M. O.; Wendling, P.

    2015-08-01

    Removal of the long-lived 222Rn daughters (210Pb, 210Bi and 210Po) from copper, stainless steel and germanium surfaces was investigated. As cleaning techniques etching and electro-polishing was applied to samples in a form of discs exposed earlier to a strong radon source. Reduction of the 210Pb activity was tested using a HPGe spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer was used. According to the conducted measurements electro-polishing was always more efficient compared to etching and in case of copper the activity reduction factors for 210Pb, 210Bi and 210Po were between 200 and 400. Etching does not remove 210Po from copper but works very efficiently from germanium. Results obtained for 210Pb and 210Bi for etched stainless steel were worse but still slightly better than those achieved for copper.

  2. [sup 222]Rn dosimetry in the dog lung

    SciTech Connect

    Harley, N.H.; Meyers, O.A.; Robbins, E.S.

    1991-01-01

    The alpha dose to cells in bronchial airways in the beagle dog during historical exposures to [sup 222]Rn decay products is calculated using updated information on airway morphometry, call nucleus depth, mucus thickness, physical dosimetry and atmospheric characteristics. The alpha dose per unit exposure to basal call nuclei in the upper airways ranges from 2 to 7 mGy WLM[sup [minus]1] (excluding the trachea) depending upon the exposure protocol used. The dose to alveolar tissue is 3 mGy WLM[sup [minus]1]. In the human lung, the dose factor for the bronchial airways is 9 mGy WLM[sub [minus]1] and for the pulmonary parenchyma 0.5 mGy WLM[sup [minus]1] The human tumors appear primarily in the first few branching airway generations while the only tumors observed in the animals were in the bronchioloalveolar region suggesting a difference in cell sensitivity to alpha radiation.

  3. {sup 222}Rn dosimetry in the dog lung

    SciTech Connect

    Harley, N.H.; Meyers, O.A.; Robbins, E.S.

    1991-12-31

    The alpha dose to cells in bronchial airways in the beagle dog during historical exposures to {sup 222}Rn decay products is calculated using updated information on airway morphometry, call nucleus depth, mucus thickness, physical dosimetry and atmospheric characteristics. The alpha dose per unit exposure to basal call nuclei in the upper airways ranges from 2 to 7 mGy WLM{sup {minus}1} (excluding the trachea) depending upon the exposure protocol used. The dose to alveolar tissue is 3 mGy WLM{sup {minus}1}. In the human lung, the dose factor for the bronchial airways is 9 mGy WLM{sub {minus}1} and for the pulmonary parenchyma 0.5 mGy WLM{sup {minus}1} The human tumors appear primarily in the first few branching airway generations while the only tumors observed in the animals were in the bronchioloalveolar region suggesting a difference in cell sensitivity to alpha radiation.

  4. Removal of {sup 222}Rn daughters from metal surfaces

    SciTech Connect

    Zuzel, G.; Wojcik, M.; Majorovits, B.; Lampert, M. O.; Wendling, P.

    2015-08-17

    Removal of the long-lived {sup 222}Rn daughters ({sup 210}Pb, {sup 210}Bi and {sup 210}Po) from copper, stainless steel and germanium surfaces was investigated. As cleaning techniques etching and electro-polishing was applied to samples in a form of discs exposed earlier to a strong radon source. Reduction of the {sup 210}Pb activity was tested using a HPGe spectrometer, for {sup 210}Bi a beta spectrometer and for {sup 210}Po an alpha spectrometer was used. According to the conducted measurements electro-polishing was always more efficient compared to etching and in case of copper the activity reduction factors for {sup 210}Pb, {sup 210}Bi and {sup 210}Po were between 200 and 400. Etching does not remove {sup 210}Po from copper but works very efficiently from germanium. Results obtained for {sup 210}Pb and {sup 210}Bi for etched stainless steel were worse but still slightly better than those achieved for copper.

  5. 230Th, 226Ra and 222Rn in abyssal sediments

    NASA Astrophysics Data System (ADS)

    Kadko, David

    1980-09-01

    A model that predicts the flux of 222Rn out of deep-sea sediment is presented. The radon is ultimately generated by 230Th which is stripped from the overlying water into the sediment. Data from many authors are compared with the model predictions. It is shown that the continental contribution of ionium is not significant, and that at low sedimentation rates, biological mixing and erosional processes strongly affect the surface concentration of the ionium. Two cores from areas of slow sediment accumulation, one from a manganese nodule region of the central Pacific and one from the Rio Grande Rise in the Atlantic were analyzed at closely spaced intervals for 230Th, 226Ra, and 210Pb. The Pacific core displayed evidence of biological mixing down to 12 cm and had a sedimentation rate of only 0.04 cm/kyr. The Atlantic core seemed to be mixed to 8 cm and had a sedimentation rate of 0.07 cm/kyr. Both cores had less total excess 230Th than predicted. Radium sediment profiles are generated from the 230Th model. Adsorbed, dissolved, and solid-phase radium is considered. According to the model, diffusional losses of radium are especially important at low sedimentation rates. Any particulate, or excess radium input is ignored in this model. The model fits the two analyzed cores if the fraction of total radium available for adsorption-desorption is about 0.5-0.7, and if K, the distribution coefficient, is about 1000. Finally, the flux of radon out of the sediments is derived from the model-generated radium profiles. It is shown that the resulting standing crop of 222Rn in the overlying water may be considered as an added constraint in budgeting 230Th and 226Ra in deep-sea sediments.

  6. 222Rn transport in a fractured crystalline rock aquifer: Results from numerical simulations

    USGS Publications Warehouse

    Folger, P.F.; Poeter, E.; Wanty, R.B.; Day, W.; Frishman, D.

    1997-01-01

    Dissolved 222Rn concentrations in ground water from a small wellfield underlain by fractured Middle Proterozoic Pikes Peak Granite southwest of Denver, Colorado range from 124 to 840 kBq m-3 (3360-22700 pCi L-1). Numerical simulations of flow and transport between two wells show that differences in equivalent hydraulic aperture of transmissive fractures, assuming a simplified two-fracture system and the parallel-plate model, can account for the different 222Rn concentrations in each well under steady-state conditions. Transient flow and transport simulations show that 222Rn concentrations along the fracture profile are influenced by 222Rn concentrations in the adjoining fracture and depend on boundary conditions, proximity of the pumping well to the fracture intersection, transmissivity of the conductive fractures, and pumping rate. Non-homogeneous distribution (point sources) of 222Rn parent radionuclides, uranium and 226Ra, can strongly perturb the dissolved 222Rn concentrations in a fracture system. Without detailed information on the geometry and hydraulic properties of the connected fracture system, it may be impossible to distinguish the influence of factors controlling 222Rn distribution or to determine location of 222Rn point sources in the field in areas where ground water exhibits moderate 222Rn concentrations. Flow and transport simulations of a hypothetical multifracture system consisting of ten connected fractures, each 10 m in length with fracture apertures ranging from 0.1 to 1.0 mm, show that 222Rn concentrations at the pumping well can vary significantly over time. Assuming parallel-plate flow, transmissivities of the hypothetical system vary over four orders of magnitude because transmissivity varies with the cube of fracture aperture. The extreme hydraulic heterogeneity of the simple hypothetical system leads to widely ranging 222Rn values, even assuming homogeneous distribution of uranium and 226Ra along fracture walls. Consequently, it is

  7. Outdoor (222)Rn-concentrations in Germany - part 2 - former mining areas.

    PubMed

    Kümmel, M; Dushe, C; Müller, S; Gehrcke, K

    2014-06-01

    In the German Federal States of Saxony, Saxony-Anhalt and Thuringia, centuries of mining and milling activities resulted in numerous residues with increased levels of natural radioactivity such as waste rock dumps and tailings ponds. These may have altered potential radiation exposures of the population significantly. Especially waste rock dumps from old mining activities as well as 20th century uranium mining may, due to their radon ((222)Rn) exhalation capacity, lead to significant radiation exposures. They often lie close to or within residential areas. In order to study the impact on the natural radon level, the Federal Office for Radiation Protection (BfS) has run networks of radon measurement points in 16 former mining areas, together with 2 networks in regions not influenced by mining for comparison purposes. Representative overviews of the long-term outdoor radon concentrations could be established including estimates of regional background concentrations. Former mining and milling activities did not result in large-area impacts on the outdoor radon level. However, significantly increased radon concentrations were observed in close vicinity of shafts and large waste rock dumps. They are partly located in residential areas and need to be considered under radiation protection aspects. Examples are given that illustrate the consequences of the Wismut Ltd. Company's reclamation activities on the radon situation.

  8. Electret ion chamber radon monitors measure dissolved 222Rn in water.

    PubMed

    Kotrappa, P; Jester, W A

    1993-04-01

    This paper describes a simple and relatively inexpensive method of determining the concentration of dissolved 222Rn in water. The method involves a recently developed electret-passive environmental radon monitor, which uses an electret ion chamber. The procedure consists of sealing a known volume of a carefully collected water sample with one of these monitors in an exposure container and determining the average equilibrium 222Rn gas concentration in the air phase during the exposure time period. This average concentration can then be used to calculate the 222Rn concentration in the original water sample. Identical samples were analyzed both by this new method and by a standard liquid scintillation method, and the results were compared over a wide range of 222Rn concentrations. There was good agreement except that the electret ion chamber method gave results that were consistently lower by about 15%. This bias in the results was attributed to both 222Rn losses during sample handling and possibly to some errors in the assumptions made in the theoretical model. A correction factor is recommended to bring the results of this technique into agreement with the standard method. The procedures are simple and economical and can be easily employed by many primary 222Rn-measuring laboratories currently using these monitors for measuring indoor 222Rn.

  9. Study of the occurrence of 222Rn and 226Ra in drinking water in Spain.

    PubMed

    Soto, J; Fernández, P L; Gómez, J; Ródenas, C

    1995-12-01

    With the aim of determining the contribution of water to the background of natural radiation in Spain, the 222Rn concentration levels were measured in domestic drinking water from a large part of the country. The water analyzed, both surface and groundwater, was collected in two areas of very distinct geological characteristics, pre-selected for the likelihood of their containing high levels of 222Rn. This water was measured using a coaxial detector of high purity Ge. The overall results demonstrate a log-normal distribution of 222Rn levels, with a geometric and arithmetic means of 10 and 381 Bq L-1, respectively, and a range between detection limit of 2 Bq L-1 and a maximum of 31,000 Bq L-1. The 222Rn concentrations measured in surface water are generally below the detection limit. Significant differences have been found depending on the geological characteristics of the area of reference, although the very distinct concentration levels of 222Rn found in samples of similar lithology imply the influence of more complex factors in the solution of 222Rn in water. Due to the relationship between radon and 226Ra, the concentration of the latter was measured in the same water using radiochemical separation and a scintillation ZnS(Ag) detector. No significant correlation between 226Ra and 222Rn concentrations has been observed unless measurements carried out in a high background radiation region are considered separately.

  10. Study of 222Rn Absorption and Detection Properties of EJ-212 and BC-400 Plastic Scintillators

    NASA Astrophysics Data System (ADS)

    Mitev, Krasimir; Dutsov, Chavdar; Georgiev, Strahil; Tsankov, Ludmil; Boshkova, Tatiana

    2017-06-01

    This paper presents a study of the 222Rn absorption properties of EJ-212 and BC-400 plastic scintillators (PSs). The diffusion length and the partition coefficient of 222Rn from air are determined at T = 21°C, which fully characterize the radon absorption properties of these PS at this temperature. The pulseshape discrimination (PSD) properties of the PS and their energy resolution are studied experimentally. It is found that PSD is applicable to discriminate between the α- and β-pulses of the 222Rn and its short-lived progeny absorbed in the volume of the PS and that the α-peaks energy resolution of PS is the same as that of a liquid scintillation cocktail. The steady-state 222Rn diffusion in plate-parallel PS is studied and the transient time needed to reach it is estimated. Examples of steady-state distributions of the 222Rn activity concentration in the volume of PS are presented and discussed. The results of this study have two applications: for the measurement of 222Rn in air by absorption in EJ-212 or BC-400 PSs and for the estimation of the contribution of 222Rn to the background signal when the PSs are used for other measurements like low-background measurements and portal monitoring.

  11. (220)Rn/(222)Rn isotope pair as a natural proxy for soil gas transport.

    PubMed

    Huxol, Stephan; Brennwald, Matthias S; Henneberger, Ruth; Kipfer, Rolf

    2013-12-17

    Radon (Rn) is a naturally occurring radioactive noble gas, which is ubiquitous in soil gas. Especially, its long-lived isotope (222)Rn (half-life: 3.82 d) gained widespread acceptance as a tracer for gas transport in soils, while the short-lived (220)Rn (half-life: 55.6 s) found less interest in environmental studies. However, in some cases, the application of (222)Rn as a tracer in soil gas is complex as its concentrations can be influenced by changes of the transport conditions or of the (222)Rn production of the soil material. Due to the different half-lives of (220)Rn and (222)Rn, the distances that can be traveled by the respective isotopes before decay differ significantly, with (220)Rn migrating over much shorter distances than (222)Rn. Therefore, the soil gas concentrations of (220)Rn and (222)Rn are influenced by processes on different length scales. In laboratory experiments in a sandbox, we studied the different transport behaviors of (220)Rn and (222)Rn resulting from changing the boundary conditions for diffusive transport and from inducing advective gas movements. From the results gained in the laboratory experiments, we propose the combined analysis of (220)Rn and (222)Rn to determine gas transport processes in soils. In a field study on soil gases in the cover soil of a capped landfill we applied the combined analysis of (220)Rn and (222)Rn in soil gas for the first time and showed the feasibility of this approach to characterize soil gas transport processes.

  12. Radon (222Rn) in ground water of fractured rocks: A diffusion/ion exchange model

    USGS Publications Warehouse

    Wood, W.W.; Kraemer, T.F.; Shapiro, A.

    2004-01-01

    Ground waters from fractured igneous and high-grade sialic metamorphic rocks frequently have elevated activity of dissolved radon (222Rn). A chemically based model is proposed whereby radium (226Ra) from the decay of uranium (238U) diffuses through the primary porosity of the rock to the water-transmitting fracture where it is sorbed on weathering products. Sorption of 226Ra on the fracture surface maintains an activity gradient in the rock matrix, ensuring a continuous supply of 226Ra to fracture surfaces. As a result of the relatively long half-life of 226Ra (1601 years), significant activity can accumulate on fracture surfaces. The proximity of this sorbed 226Ra to the active ground water flow system allows its decay progeny 222Rn to enter directly into the water. Laboratory analyses of primary porosity and diffusion coefficients of the rock matrix, radon emanation, and ion exchange at fracture surfaces are consistent with the requirements of a diffusion/ion- exchange model. A dipole-brine injection/withdrawal experiment conducted between bedrock boreholes in the high-grade metamorphic and granite rocks at the Hubbard Brook Experimental Forest, Grafton County, New Hampshire, United States (42??56???N, 71??43???W) shows a large activity of 226Ra exchanged from fracture surfaces by a magnesium brine. The 226Ra activity removed by the exchange process is 34 times greater than that of 238U activity. These observations are consistent with the diffusion/ion-exchange model. Elutriate isotopic ratios of 223Ra/226Ra and 238U/226Ra are also consistent with the proposed chemically based diffusion/ion-exchange model.

  13. Radon (222Rn) in ground water of fractured rocks: a diffusion/ion exchange model.

    PubMed

    Wood, Warren W; Kraemer, Thomas F; Shapiro, Allen

    2004-01-01

    Ground waters from fractured igneous and high-grade sialic metamorphic rocks frequently have elevated activity of dissolved radon (222Rn). A chemically based model is proposed whereby radium (226Ra) from the decay of uranium (238U) diffuses through the primary porosity of the rock to the water-transmitting fracture where it is sorbed on weathering products. Sorption of 226Ra on the fracture surface maintains an activity gradient in the rock matrix, ensuring a continuous supply of 226Ra to fracture surfaces. As a result of the relatively long half-life of 226Ra (1601 years), significant activity can accumulate on fracture surfaces. The proximity of this sorbed 226Ra to the active ground water flow system allows its decay progeny 222Rn to enter directly into the water. Laboratory analyses of primary porosity and diffusion coefficients of the rock matrix, radon emanation, and ion exchange at fracture surfaces are consistent with the requirements of a diffusion/ion-exchange model. A dipole-brine injection/withdrawal experiment conducted between bedrock boreholes in the high-grade metamorphic and granite rocks at the Hubbard Brook Experimental Forest, Grafton County, New Hampshire, United States (42 degrees 56'N, 71 degrees 43'W) shows a large activity of 226Ra exchanged from fracture surfaces by a magnesium brine. The 226Ra activity removed by the exchange process is 34 times greater than that of 238U activity. These observations are consistent with the diffusion/ion-exchange model. Elutriate isotopic ratios of 223Ra/226Ra and 238U/226Ra are also consistent with the proposed chemically based diffusion/ion-exchange model.

  14. Online ^{222}Rn removal by cryogenic distillation in the XENON100 experiment

    NASA Astrophysics Data System (ADS)

    Aprile, E.; Aalbers, J.; Agostini, F.; Alfonsi, M.; Amaro, F. D.; Anthony, M.; Arneodo, F.; Barrow, P.; Baudis, L.; Bauermeister, B.; Benabderrahmane, M. L.; Berger, T.; Breur, P. A.; Brown, A.; Brown, E.; Bruenner, S.; Bruno, G.; Budnik, R.; Bütikofer, L.; Calvén, J.; Cardoso, J. M. R.; Cervantes, M.; Cichon, D.; Coderre, D.; Colijn, A. P.; Conrad, J.; Cussonneau, J. P.; Decowski, M. P.; de Perio, P.; Gangi, P. Di; Giovanni, A. Di; Diglio, S.; Duchovni, E.; Eurin, G.; Fei, J.; Ferella, A. D.; Fieguth, A.; Franco, D.; Fulgione, W.; Gallo Rosso, A.; Galloway, M.; Gao, F.; Garbini, M.; Geis, C.; Goetzke, L. W.; Grandi, L.; Greene, Z.; Grignon, C.; Hasterok, C.; Hogenbirk, E.; Itay, R.; Kaminsky, B.; Kessler, G.; Kish, A.; Landsman, H.; Lang, R. F.; Lellouch, D.; Levinson, L.; Calloch, M. Le; Lin, Q.; Lindemann, S.; Lindner, M.; Lopes, J. A. M.; Manfredini, A.; Maris, I.; Undagoitia, T. Marrodán; Masbou, J.; Massoli, F. V.; Masson, D.; Mayani, D.; Meng, Y.; Messina, M.; Micheneau, K.; Miguez, B.; Molinario, A.; Murra, M.; Naganoma, J.; Ni, K.; Oberlack, U.; Orrigo, S. E. A.; Pakarha, P.; Pelssers, B.; Persiani, R.; Piastra, F.; Pienaar, J.; Piro, M.-C.; Pizzella, V.; Plante, G.; Priel, N.; Rauch, L.; Reichard, S.; Reuter, C.; Rizzo, A.; Rosendahl, S.; Rupp, N.; Saldanha, R.; dos Santos, J. M. F.; Sartorelli, G.; Scheibelhut, M.; Schindler, S.; Schreiner, J.; Schumann, M.; Lavina, L. Scotto; Selvi, M.; Shagin, P.; Shockley, E.; Silva, M.; Simgen, H.; Sivers, M. v.; Stein, A.; Thers, D.; Tiseni, A.; Trinchero, G.; Tunnell, C.; Upole, N.; Wang, H.; Wei, Y.; Weinheimer, C.; Wulf, J.; Ye, J.; Zhang, Y.; Cristescu, I.

    2017-06-01

    We describe the purification of xenon from traces of the radioactive noble gas radon using a cryogenic distillation column. The distillation column was integrated into the gas purification loop of the XENON100 detector for online radon removal. This enabled us to significantly reduce the constant ^{222}Rn background originating from radon emanation. After inserting an auxiliary ^{222}Rn emanation source in the gas loop, we determined a radon reduction factor of R > 27 (95% C.L.) for the distillation column by monitoring the ^{222}Rn activity concentration inside the XENON100 detector.

  15. Summertime elevation of sup 222 Rn levels in Huntsville, Alabama

    SciTech Connect

    Wilson, D.L.; Gammage, R.B.; Dudney, C.S.; Saultz, R.J. )

    1991-02-01

    Indoor Rn concentrations and Rn in adjacent karst terrains were studied at four houses with crawlspaces in Huntsville, AL. In warm summertime weather, Rn-rich air may vent through limestone solution cavities exposed as holes at the surface of the properties. A probable interrelated-finding is that the indoor levels of {sup 222}Rn are distinctly higher in the summer than winter. The karst underlying the homes is structurally faulted and, in all probability, facilitates Rn transport from the solution cavities to the crawlspaces. Abrupt day-to-day changes in indoor Rn concentrations were recorded in addition to large seasonal changes. If the owners or residents of these particular homes had attempted to make, and interpret, short-term screening measurements for Rn during the fall season, problems, including false negatives, could have arisen because of order-of-magnitude changes in Rn concentration occurring over a few days. The best time of year to make screening measurements would be during the summer when indoor Rn concentrations are more likely to reach their maximum values.

  16. Theoretical evaluation of the 222Rn emanation coefficient for coal fly ash.

    PubMed

    Maraziotis, E A

    1987-03-01

    The release of 222Rn, from individual material grains in which it is formed, may be largely a diffusion process. This paper presents an analytical model purporting to describe the physical process of the release of 222Rn atoms from a 226Ra-bearing material grain. The solution of the diffusion equation for a spherical grain permits us to calculate theoretically the diffusion and emanation coefficient. Using this analysis to interpret experimental release data is explained.

  17. Exploring heterogeneities in a stressed alluvial aquifer using 222Rn concentrations in groundwater

    NASA Astrophysics Data System (ADS)

    Hillman, C. A.

    2016-12-01

    Understanding aquifer characteristics is important for determining the nature of groundwater flow and contaminant transport in the subsurface. Even if an alluvial aquifer can be considered homogeneous on a macro scale, groundwater models often fail to account for local heterogeneities in aquifer porosity and hydraulic conductivity. This study explores the use of 222Rn concentrations in groundwater in discerning heterogeneities in alluvial aquifer textures. The utility of 222Rn for studying the subsurface is based on its ubiquity in most rock types, its short half life (3.8 days) and its non-reactive nature. 226Ra, the direct progenitor, supplies a constant source of 222Rn to pore water and the rapid decay of 222Rn results in secular equilibrium in pore water in about 20 days. Irregularities in 222Rn concentrations throughout the aquifer may indicate differences in emanation source or emanation strength of the matrix, which is inversely related to porosity (i.e., the surface area within the recoil range of 222Rn). For this study, groundwater samples were collected from the Palo Verde Valley, a floodplain aquifer along the Colorado River in Riverside County, California. Samples were collected between 2007 and 2014 and 222Rn concentrations range from 160 to 1470 pCi/L with most samples falling between 250 and 1050 pCi/L. There is a strong positive correlation between well depth and 222Rn concentration indicating an increase in fine grained units (silts and clays) with depth. Laterally, a cluster of higher values occurs in the northeast quadrant of the study area adjacent to the river. Among the cluster of high values, though, is a sample with only 160 pCi/L possibly representing the presence of coarse-grained channel deposits.

  18. Soil water effects on concentration profiles and variations of 222Rn in a vadose zone.

    PubMed

    Fukui, M

    1987-08-01

    Concentration profiles of 222Rn and their variations were studied to understand the vertical motion in the ground caused by fluctuations of meteorological parameters, such as precipitation, ground-water level and atmospheric pressure. A method of trapping 222Rn was developed to measure the concentration profiles by circulating and bubbling soil gas in porous cups into toluene. For locations where the water table is close to the surface, observations showed a peak concentration in the vertical profile of 222Rn at about a 40-cm depth and revealed that the concentration in soil gas decreases as soil moisture increases near the water table. Soil gas in a buried vessel also was circulated continuously to monitor 222Rn in the ground air near the surface using an ionization chamber. A rising of the water table following precipitation causes a burst of 222Rn concentration by upflow in the ground, though the concentration in the soil gas soon decreases with the intake of air above the surface due to increasing atmospheric pressure following precipitation. The concentration in soil gas again increases via the phenomenon accompanying the recovery of equilibrium in soil water between 222Rn and 226Ra.

  19. 222Rn and 220Rn concentrations in soil gas of Karkonosze-Izera Block (Sudetes, Poland).

    PubMed

    Malczewski, Dariusz; Zaba, Jerzy

    2007-01-01

    Soil gas 222Rn and 220Rn concentrations were measured at 18 locations in the Karkonosze-Izera Block area in southwestern Poland. Measurements were carried out in surface air and at sampling depths of 10, 40 and 80 cm. Surface air 222Rn concentrations ranged from 4 to 2160 Bq m(-3) and 220Rn ranged from 4 to 228 Bq m(-3). The concentrations for 10 and 40 cm varied from 142 Bq m(-3) to 801 kBq m(-3) and 102 Bq m(-3) to 64 kBq m(-3) for 222Rn and 220Rn, respectively. At 80 cm 222Rn concentrations ranged from 94 Bq m(-3) to >1 MBq m(-3). The 220Rn concentrations at 80 cm varied from 45 Bq m(-3) to 48 kBq m(-3). The concentration versus depth profiles for 222Rn differed for soils developed on fault zones, uranium deposits or both. Atmospheric air temperature and soil gas 222Rn and 220Rn were negatively correlated. At sampling sites with steep slopes, 220Rn concentrations decreased with depth.

  20. Standards, calibration and quality assurance of 222Rn measurements in Sweden

    NASA Astrophysics Data System (ADS)

    Falk, R.; Hagberg, N.; Mjönes, L.; Möre, H.; Nyblom, L.; Swedjemark, G. A.

    1994-01-01

    Inhaled decay products of 222Rn are the dominant components of the natural radiation exposure to the general population. Limits have been introduced in Sweden, and recommendations were made in 1980 for decreasing indoor 222Rn concentration. The need for the coordinated calibration of measuring instruments as well as for quality assurance was obvious for both health and economic reasons. 222Rn measurements in Sweden are based on standards traceable to the National Institute of Standard and Technology (NIST) through the use of standard reference material 226Ra. Standards for both 222Rn and short-lived 222Rn progeny are described together with the reference instrument adopted for these studies. The calibration of field instruments was performed in a "radon room", a climate chamber in which it is possible to vary and monitor the concentration of 222Rn as well as other characteristics of the indoor air such as temperature, humidity, ventilation rate and aerosol concentration. The rules and regulations for field measurements imply a calibration of the instruments yearly, as well as accreditation and training for the companies that carry out the measurements. Examples are given of the official measurement protocols used for the different types of instruments.

  1. Measurement of {sup 222}Rn flux, {sup 222}Rn emanation and {sup 226}Ra concentration from injection well pipe scale

    SciTech Connect

    Rood, A.S.; Kendrick, D.T.

    1996-02-01

    The presence of Naturally Occurring Radioactive Material (NORM) has been recognized since the early 1930s in petroleum reservoirs and in oil and gas production and processing facilities. NORM was typically observed in barite scale that accumulated on the interior of oil production tubing and in storage tank and heater-treater separation sludge. Recent concern has been expressed over the health impacts from the uncontrolled release of NORM to the public. There are several potential exposure pathways to humans from oil-field NORM. Among these is inhalation of radon gas and its daughter products. For this exposure pathway to be of any significance, radon must first be released from the NORM matrix and diffuse in free air. The radon emanation fraction refers to the fraction of radon atoms produced by the decay of radium, that migrate from the bulk material as free gaseous atoms. The purpose of this investigation was to characterize the radon release rates from NORM-scale contaminated production tubing being stored above ground, characterize the radon emanation fraction of the bulk scale material when removed from the tubing, and characterize the radium concentrations of the scale. Accurate characterization of {sup 222}Rn emanation fractions from pipe scale may dictate the type of disposal options available for this waste. Characterization of radon release from stored pipes will assist in determining if controls are needed for workers or members of the public downwind from the source. Due to the sensitive nature of this data, the location of this facility is not disclosed.

  2. Soil gas 222Rn concentration in northern Germany and its relationship with geological subsurface structures.

    PubMed

    Künze, N; Koroleva, M; Reuther, C-D

    2013-01-01

    (222)Rn in soil gas activity was measured across the margins of two active salt diapirs in Schleswig-Holstein, northern Germany, in order to reveal the impact of halokinetic processes on the soil gas signal. Soil gas and soil sampling were carried out in springtime and summer 2011. The occurrence of elevated (222)Rn in soil gas concentrations in Schleswig-Holstein has been ascribed to radionuclide rich moraine boulder material deposits, but the contribution of subsurface structures has not been investigated so far. Reference samples were taken from a region known for its granitic moraine boulder deposits, resulting in (222)Rn in soil gas activity of 40 kBq/m(3). The values resulting from profile sampling across salt dome margins are of the order of twice the moraine boulder material reference values and exceed 100 kBq/m(3). The zones of elevated concentrations are consistent throughout time despite variations in magnitude. One soil gas profile recorded in this work expands parallel to a seismic profile and reveals multiple zones of elevated (222)Rn activities above a rising salt intrusion. The physical and chemical properties of salt have an impact on the processes influencing gas migration and surface near radionuclide accumulations. The rise of salt supports the breakup of rock components thus leading to enhanced emanation. This work provides a first approach regarding the halokinetic contribution to the (222)Rn in soil gas occurrence and a possible theoretical model which summarizes the relevant processes was developed.

  3. Soil radon ( 222 Rn) monitoring at Furnas Volcano (São Miguel, Azores): Applications and challenges

    NASA Astrophysics Data System (ADS)

    Silva, C.; Ferreira, T.; Viveiros, F.; Allard, P.

    2015-05-01

    A soil 222Rn continuous monitoring test was performed in three sampling points inside Furnas Volcano caldera and 222Rn concentration varied between 0 and 153000 Bq/m3. Multivariate regression and spectral analyses were applied to the time series registered in order to understand and filter the influence of external factors on soil 222Rn concentration and to recognise anomalies correlated with deep processes. The regression models show that barometric pressure, soil water content, soil temperature, soil CO2 flux, air temperature, relative air humidity and wind speed are the statistical meaningful variables explaining between 15.8% and 73.6% of 222Rn variations. Spectral analysis allowed to identify seasonal variations and daily variations associated with one cycle per day on winter months only in one of the monitored sites. This diurnal variation is correlated with air temperature, relative air humidity and wind speed cycles. The change in the location of the sampling points was caused by both artificial and natural constrains. On the three monitoring sites, after a period of continuous register, a sudden drop on the 222Rn concentration values was observed and the cause is still under debate. The work performed can be applied for seismovolcanic monitoring and for public health risk assessment.

  4. Direct determination of /sup 222/Rn gas using the electret to remove daughters at formation

    SciTech Connect

    Harley, N.H.

    1981-01-01

    Five compact, portable, continuous /sup 222/Rn monitors have been constructed inhouse. Printed data can be obtained from intervals ranging from 10 minutes to 990 minutes. One hour count interval provides a lower limit of detection of 0.03 pCi /sup 222/Rn/l/sup -1/ which is sufficient for measurement of any environmental level encountered. Calibration of the units was accomplished in the EML radon calibration room and the typical calibration factor is 165 counts per hour per pCi /sup 222/Rn/l. The units are now being field tested. Two indoor/outdoor pairs are located in a single family dwelling and in a high rise apartment. One unit is being used for special studies.

  5. A novel application for 222Rn emanation standards: radon-cryptophane host chemistry.

    PubMed

    Laureano-Perez, L; Collé, R; Jacobson, D R; Fitzgerald, R; Khan, N S; Dmochowski, I J

    2012-09-01

    In collaboration with the University of Pennsylvania, a (222)Rn emanation source was used for the determination of the binding affinity of radon to a cryptophane molecular host. This source was similar to a (222)Rn emanation standard that was developed and disseminated by the National Institute of Standards and Technology (NIST). The novel experimental design involved performing the reactions at femtomole levels, developing exacting gravimetric sampling methods and making precise (222)Rn assays by liquid scintillation counting. A cryptophane-radon association constant was determined, K(A)=(49,000±12,000) L mol(-1) at 293 K, which was the first measurement of radon binding to a molecular host.

  6. Determination of 222Rn emanation fraction and diffusion coefficient in concrete using accumulation chambers and the influence of humidity and radium distribution.

    PubMed

    Cosma, C; Dancea, F; Jurcut, T; Ristoiu, D

    2001-03-01

    In this paper we present a laboratory method for the determination of diffusion coefficient, D, as well as the 222Rn emanation fraction, f, in concrete core samples. It is based either on the analyses of the growth curves of the radon in the air volume surrounding a sample enclosed in an accumulation chamber (Lucas cell or RADIM device) or using the charcoal adsorption method. Samples used have a special geometry allowing the assumption of a one-dimensional diffusion of radon in material. Radium was enhanced in the concrete samples by adding radium bromide solution or uranium ore. A strong dependence of the emanation fraction on the enhancing method was observed. For the sample enhanced with uranium ore the specific exhalation rate was about ten times smaller. A marked dependence of radon exhalation on the water content was also observed.

  7. Using (222)Rn as a tracer of geodynamical processes in underground environments.

    PubMed

    Valladares, D L; da Silva, A A R; Lacerda, T; Anjos, R M; Rizzotto, M; Velasco, H; de Rosas, J P; Tognelli, G; Yoshimura, E M; Ayub, J Juri

    2014-01-15

    Radon levels in two old mines in San Luis, Argentina, were measured and analyzed, with the aim to assess the potential use of this radioactive noble gas as a tracer of geological processes in underground environments. La Carolina gold mine and Los Cóndores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, higher concentration values of (222)Rn were observed in summer than in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Cóndores mine. The pattern of radon transport inside La Carolina mine revealed, contrary to what was believed, that this mine behaves as a system with two entrances located at different levels. However, this feature can only be observed in the winter season, when there is a marked difference between the inside and outside temperatures of the mine. In the case of Los Cóndores mine, the radon concentration pattern distribution is principally established by air current due to chimney-effect in summer and winter seasons. In both cases, the analyses of radon pattern distribution appear as a good method to trace air currents, and then localize unknown ducts, fissures or secondary tunnels in subterranean environments.

  8. Utility of 222Rn as a passive tracer of subglacial distributed system drainage

    NASA Astrophysics Data System (ADS)

    Linhoff, Benjamin S.; Charette, Matthew A.; Nienow, Peter W.; Wadham, Jemma L.; Tedstone, Andrew J.; Cowton, Thomas

    2017-03-01

    Water flow beneath the Greenland Ice Sheet (GrIS) has been shown to include slow-inefficient (distributed) and fast-efficient (channelized) drainage systems, in response to meltwater delivery to the bed via both moulins and surface lake drainage. This partitioning between channelized and distributed drainage systems is difficult to quantify yet it plays an important role in bulk meltwater chemistry and glacial velocity, and thus subglacial erosion. Radon-222, which is continuously produced via the decay of 226Ra, accumulates in meltwater that has interacted with rock and sediment. Hence, elevated concentrations of 222Rn should be indicative of meltwater that has flowed through a distributed drainage system network. In the spring and summer of 2011 and 2012, we made hourly 222Rn measurements in the proglacial river of a large outlet glacier of the GrIS (Leverett Glacier, SW Greenland). Radon-222 activities were highest in the early melt season (10-15 dpm L-1), decreasing by a factor of 2-5 (3-5 dpm L-1) following the onset of widespread surface melt. Using a 222Rn mass balance model, we estimate that, on average, greater than 90% of the river 222Rn was sourced from distributed system meltwater. The distributed system 222Rn flux varied on diurnal, weekly, and seasonal time scales with highest fluxes generally occurring on the falling limb of the hydrograph and during expansion of the channelized drainage system. Using laboratory based estimates of distributed system 222Rn, the distributed system water flux generally ranged between 1-5% of the total proglacial river discharge for both seasons. This study provides a promising new method for hydrograph separation in glacial watersheds and for estimating the timing and magnitude of distributed system fluxes expelled at ice sheet margins.

  9. Measurements of soil and canopy exchange rates in the Amazon rain forest using sup 222 Rn

    SciTech Connect

    Trumbore, S.E. Lamont-Doherty Geological Observatory, Palisades, NY ); Keller, M. ); Wofsy, S.C. ); Da Costa, J.M. )

    1990-09-20

    Measurements of the emission of {sup 222}Rn from Amazon forest soils, and profiles of {sup 222}Rn in air were used to study the ventilation of the soil atmosphere and the nocturnal forest canopy. The emission of {sup 222}Rn from the yellow clay soils dominant in the study area averaged 0.38 {plus minus} 0.07 atom cm{sup {minus}2} s{sup {minus}1}. Nearby sand soils had similar fluxes, averaging 0.30 {plus minus} 0.07 atom cm{sup {minus}2} s{sup {minus}1}. The effective diffusivity in the clay soil (0.008 {plus minus} 0.004 cm{sup 2} s{sup {minus}1}), was lower than that for the sand soil (0.033 {plus minus} 0.030 cm{sup 2} s{sup {minus}1}). Profiles of {sup 222}Rn and CO{sub 2} in air showed steepest concentration gradients in the layer between 0 and 3 m above the soil surface. Aerodynamic resistances calculated for this layer from {sup 222}Rn and CO{sub 2} varied from 1.6 to 18 s cm{sup {minus}1}, with greater resistance during the afternoon than at night. Time averaged profiles of {sup 222}Rn in the forest canopy measured during the evening and night were combined with the soil flux measurements to compute the resistance of the subcanopy to exchange with overlying air. The integrated nocturnal rate of gas exchange between the canopy layer (0 to 41 m) and overlying atmosphere based on {sup 222}Rn averaged 0.33 {plus minus} 0.15 cm s{sup {minus}1}. An independent estimate of gas exchange, based on 13 nights of CO{sub 2} profiles, averaged 0.21 {plus minus} 0.40 cm s{sup {minus}1}. These exchange rates correspond to flushing times for the 41 m canopy layer of 3.4 and 5.5 hours, respectively. Comparison of {sup 222}Rn and CO{sub 2} profiles show that the nocturnal production of CO{sub 2} by above-ground vegetation was about 20% of the soil emission source, consistent with data from eddy-correlation experiments.

  10. Quantifying Groundwater Flow to a Subtropical Spring-fed River Using Automated 222Rn Measurement

    NASA Astrophysics Data System (ADS)

    Khadka, M. B.; Martin, J. B.

    2014-12-01

    The magnitude of groundwater discharge to streams can alter stream water chemistry, thereby affecting riverine ecosystems and surface water quality. Point groundwater discharge to streams can be measured using a variety of techniques; however, integrating point and diffuse discharge is difficult over large stream reaches. We applied an automated radon-in-water technique for continuous measurements of 222Rn activities along a 5 km length of the spring-fed Ichetucknee River in north-central Florida. Integration of longitudinal 222Rn distribution, measured on three separate occasions, with groundwater and spring water end members in a mass balance equation allowed temporal and spatial assessment of groundwater flow to the stream. The 222Rn activities indicate groundwater fluxes are higher in the upper reach of the river, which has a narrow flood plain, than in the lower reach, with a wide flood plain. A wide flood plain enhances evapotranspiration, which may cause the observed difference in groundwater seepage. Groundwater flow to the upper reach increases following rain events as diffuse recharge within the catchment increases hydraulic gradients toward the river. Groundwater recharge to the lower reach is smaller and less variable than the upper reach regardless of the river flow. The lower reach can back flood when the Santa Fe River, the receiving stream, floods because of the low gradient of the Ichetucknee River (<2 m/km). Back flooding reduces flow, increases water level and inundates the floodplain, reducing the hydraulic head gradient and groundwater inflow. Based on the 222Rn mass balance, cumulative groundwater inflow is estimated to be 2.5 ± 1 m3/s (±SD) during low flow and 3.2 ± 1.5 m3/s during high flow. The estimated ground water inflows to the Ichetucknee River from the 222Rn mass balance are about twice the estimates of 1.2 m3/s and 1.5 m3/s obtained from dye tracer and ionic chemical tracer methods, respectively. The estimated higher fluxes from

  11. Surface radioactivity resulting from the deposition of 222Rn daughter products.

    PubMed

    Lively, R S; Ney, E P

    1987-04-01

    Studies of indoor radiation environments typically involve measurements of 222Rn, airborne 222Rn decay products, and the degree of radioactive equilibrium. This paper describes the relationship between the 222Rn in air, and the level of surface radioactivity that results from the build-up and decay of the daughter isotope, 210Pb. Samples of 222Rn were collected from Mystery Cave, which is located in southeastern Minnesota and from the basement of a house in Minneapolis, MN. Lead-210 was measured on surfaces within the cave, on a rock removed from the cave, and on a basement window. Surface alpha activities were measured on the rock sample and on the window. Radon-222 concentrations in the cave air ranged from 3 to 13 kBq m-3. In the basement, 222Rn levels were between 0.2 and 0.4 kBq m-3. Virtually all the surface radioactivity resulted from the deposition and decay of airborne 222Rn daughter products and was not produced by the decay of U in the rock. Radon-222 concentrations in the cave air were almost 30 times higher than in the basement air; however, the surface 210Pb activity in the cave was 100 times higher than that in the basement. This suggests that in the cave air, 222Rn daughter products are more likely to reach the walls and decay to 210Pb. The measurements of surface alpha activity did not show a similar trend primarily because 210Pb had diffused further into the coating of dirt on the rock than into the glass of the window. The resulting surface activity of the rock was lower than expected based on the 210Pb concentration, because many of the alpha-emitting nuclei were at depths beyond the range of emitted alpha particles. On surfaces where the penetration range of alpha particles is greater than the diffusion depth of 210Pb atoms, either the 210Pb concentration or surface alpha-activity measurements should provide estimates of average long-term 222Rn concentrations.

  12. INDOOR 222RN IN TENNESSEE VALLEY HOUSES: SEASONAL, BUILDING AND GEOLOGICAL FACTORS

    EPA Science Inventory

    A two-season survey of indoor 222Rn concentrations was conducted in 226 occupied houses in Roane County, TN, during 1985 and 1986. A similar survey of 86 houses in Madison County, AL, was conducted in 1988 and 1989. Alpha track detectors were placed in each of the houses for thre...

  13. Continuous observations of atmospheric 222Rn concentration at Lutjewad - analysis of 5 years of data

    NASA Astrophysics Data System (ADS)

    Navin Manohar, Swagath; Chen, Huilin; Meijer, Harro A. J.; Neubert, Rem; van der Laan, Sander

    2013-04-01

    Accurate representation of the turbulent physics and dynamical processes in the atmospheric boundary layer (ABL) and also the influence of meteorological conditions on the atmospheric compounds pose a huge challenge on the modeling community as many models fail to represent or even take into account of these processes properly. Continuous atmospheric observations of a radioactive tracer like radon (222Rn) combined with observed meteorological parameters can provide much valuable information about the large diurnal and seasonal variability of the ABL and the meteorological effects associated with it and also can be used for evaluation of transport schemes in regional and global circulation models. We report on the results of five years of radon time series at our atmospheric measurement station Lutjewad in The Netherlands (6° 21 E, 53° 21 N, 1 m asl, air intake at 60 m above ground). Two major periodical variation in atmospheric 222Rn concentration will be discussed in detail (i) seasonal variation with a maximum in late autumn and minimum in spring: (ii) diurnal variation, that is strongest during summer and almost non-existent during winter. In addition, the influence of different observed meteorological parameters (such as atmospheric pressure, humidity, temperature, wind direction and velocity) will also be discussed. Lastly, first results of model simulations of atmospheric 222Rn concentrations for one year using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) and a newly created 222Rn flux map will be presented.

  14. Radon (222Rn) in groundwater studies in two volcanic zones of central Mexico

    NASA Astrophysics Data System (ADS)

    Cortés, A.; Cardona, A.; Pérez-Quezadas, J.; Inguaggiato, S.; Vázquez-López, C.; Golzarri, J. I.; Espinosa, G.

    2013-07-01

    The distribution of radon (222Rn) concentrations in groundwater from two basins of volcanic origin is presented. Regions have different physiographic characteristics with fractured mafic/intermediate and felsic rocks. Samples were taken from deep wells and springs. Concentrations were field measured by two methods: i) scintillator, coupled to a photomultiplier, and ii) passive method, using Nuclear Track Detectors. Qualitatively, results of 222Rn measured with both techniques are comparable only when concentrations have values less than 1 Bq/l. For the Basin of Mexico City the data shows an average difference of 0.13 Bq/l. Results of 222Rn concentrations in 46 groundwater samples indicate that the data are below 11.1 Bq/l, with both methodologies. Low concentrations of 222Rn in the Basin of Mexico City are related to the mafic intermediate composition rocks such as basalt. The anomalies with high values are correlated with the transition zone between volcanic units and clays from ancient lakes. In San Luis Potosí 10 samples show an average of 4.2 Bq/l. These concentrations compared with those of the Basin of Mexico City are related to the composition of the felsic (rhyolite) volcanic rocks.

  15. INDOOR 222RN IN TENNESSEE VALLEY HOUSES: SEASONAL, BUILDING AND GEOLOGICAL FACTORS

    EPA Science Inventory

    A two-season survey of indoor 222Rn concentrations was conducted in 226 occupied houses in Roane County, TN, during 1985 and 1986. A similar survey of 86 houses in Madison County, AL, was conducted in 1988 and 1989. Alpha track detectors were placed in each of the houses for thre...

  16. Equilibration correction of temporal measurements for sudden 222Rn concentration changes

    NASA Astrophysics Data System (ADS)

    Tan, Y.; Tokonami, S.; Liu, H.; Kearfott, K. J.

    2016-02-01

    222Rn and 220Rn can be used as tracers of groundwater or submarine springs, and 222Rn in water also could indicate indoor radon problems in some regions. The half-life of 222Rn is long enough that its concentration may remain significant during transit over relatively long distances, while that of 220Rn is not. Prior research revealed that it took about 15 min for the radon to achieve gas equilibrium at a water flow rate of 17.5 L min-1, which is approximately equivalent to the time required for the 222Rn-218Po pair to approach radioactive equilibrium and is limiting in terms of measurements of sudden radon concentration change. In this work, an algorithm is applied to improve the continuous tracing of radon concentrations in the field environment. Results of a laboratory experiment analyzed applying the analysis method illustrated its ability to allow immediate identification of sharp concentration increases. In this paper we find that a precipitous drop in radon concentrations lead to improper corrected values as the result of measurement uncertainties prior to the drop, and a method using zero instead negative values for reducing the uncertainties under such condition also is proposed.

  17. Fresh Versus Marine Submarine Groundwater Discharge: How 222Rn Might Help Distinguish These Two Sources

    NASA Astrophysics Data System (ADS)

    Smith, C. G.; Cable, J. E.; Martin, J. B.; Roy, M.

    2008-05-01

    Pore water distributions of 222Rn (t1/2 = 3.83 d), obtained during two sampling trips 9-12 May 2005 and 6-8 May 2006, are used to determine spatial and temporal variations of fluid discharge from a seepage face located along the mainland shoreline of Indian River Lagoon, Florida. Porewater samples were collected from a 30 m transect of multi-level piezometers and analyzed for 222Rn via liquid scintillation counting; the mean of triplicate measurements was used to represent the porewater 222Rn activities. Sediment samples were collected from five vibracores (0, 10, 17.5, 20, and 30 m offshore) and emanation rates of 222Rn (sediment supported) were determined using a standard cryogenic extraction technique. A conceptual 222Rn transport model and subsequent numerical model were developed based on the vertical distribution of dissolved and sediment-supported 222Rn and applicable processes occurring along the seepage face (e.g. advection, diffusion, and nonlocal exchange). The model was solved inversely with the addition of two Monte Carlo (MC) simulations to increase the statistical reliability of three parameters: fresh groundwater seepage velocity (v), irrigation intensity (α0), and irrigation attenuation (α1). The first MC simulation ensures that the Nelder-Mead minimization algorithm converges on a global minimum of the merit function and that the parameters estimates are consistent within this global minimum. The second MC simulation provides 90% confidence intervals on the parameter estimates using the measured 222Rn activity variance. Fresh groundwater seepage velocities obtained from the model decrease linearly with distance from the shoreline; seepage velocities range between 0.6 and 42.2 cm d-1. Based on this linear relationship, the terminus of the fresh groundwater seepage is approximately 25 m offshore and total fresh groundwater discharge for the May-2005 and May-2006 sampling trips are 1.16 and 1.45 m3 d-1 m-1 of shoreline, respectively. We hypothesize

  18. Measurement of (222)Rn concentration in drinking water in Sakarya, Turkey.

    PubMed

    Yakut, Hakan; Tabar, Emre; Zenginerler, Zemine; Demirci, Nilufer; Ertugral, Filiz

    2013-12-01

    In this paper, the first measurement of (222)Rn concentrations in drinking water from wells, springs and bottled waters in the city of Sakarya, Turkey was presented. The measurements were performed using RAD 7, a solid-state alpha detector, with RAD H2O (radon in water) accessory manufactured by Durridge Company, Inc. The measured activity concentrations ranged from 1.98 to 20.80 Bq l(-1) with an average value of 9.05 Bq l(-1) for well water, from 0.75 to 59.65 Bq l(-1) with an average value of 13.78 Bq l(-1) for spring water and from 0.75 to 22.8 Bq l(-1) with an average value of 5.41 Bq l(-1) for bottled water. Although these results indicated relatively high (222)Rn concentrations compared with that from other parts of the Turkey, they are still below the World Health Organization recommended level of 100 Bq l(-1) for radon. Using the measured activities of (222)Rn, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn were estimated to range from 2.59 to 205.97 µSv y(-1), from 1.55 to 123.28 µSv y(-1) and from 1.31 to 104.48 µSv y(-1) for age groups 1-2, 8-12 and >17 y, respectively.

  19. Spatial and temporal variations of soil gas {sup 220}RN and {sup 222}RN at two sites in New Jersey

    SciTech Connect

    Hutter, A.R.

    1995-12-31

    Soil gas {sup 220}Rn and {sup 222}Rn concentrations have been measured at sites in Chester and Aberdeen. New Jersey. Two years of {sup 222}Rn and {sup 220}Rn data were obtained from a depth of 0.85 m, followed by two subsequent years from depths of 0.28, 0.56, 0.85 and 1.28 m. {sup 220}Rn and {sup 222}Rn variations before the first winter that sample tubes were installed were larger than later, indicating that the soil structure, disturbed during installation of the tubes, may significantly redistribute after the first winter, thus ensuring that the sample is drawn from near the bottom of the tube. At the Chester site, autumn {sup 222}Rn concentrations were found to be up to 10 times higher than winter values, variations larger than predicted assuming diffusion-only transport. Spatial variations up to an order of magnitude are observed over distances of a few meters. {sup 220}Rn concentrations are typically {approximately} 2 to 3 times higher during summer than during winter. At the Aberdeen site, {sup 220}Rn and {sup 222}Rn concentrations were about an order of magnitude less than the lowest Chester site values, with no statistically significant temporal or spatial variations observed. Permeability measurements, thought to be an indicator of parameters controlling soil gas {sup 222}Rn variations, show no correlation with {sup 220}Rn or {sup 222}Rn at either site.

  20. (222)Rn activity in groundwater of the St. Lawrence Lowlands, Quebec, eastern Canada: relation with local geology and health hazard.

    PubMed

    Pinti, Daniele L; Retailleau, Sophie; Barnetche, Diogo; Moreira, Floriane; Moritz, Anja M; Larocque, Marie; Gélinas, Yves; Lefebvre, René; Hélie, Jean-François; Valadez, Arisai

    2014-10-01

    One hundred ninety-eight groundwater wells were sampled to measure the (222)Rn activity in the region between Montreal and Quebec City, eastern Canada. The aim of this study was to relate the spatial distribution of (222)Rn activity to the geology and the hydrogeology of the study area and to estimate the potential health risks associated with (222)Rn in the most populated area of the Province of Quebec. Most of the groundwater samples show low (222)Rn activities with a median value of 8.6 Bq/L. Ninety percent of samples show (222)Rn activity lower than 100 Bq/L, the exposure limit in groundwater recommended by the World Health Organization. A few higher (222)Rn activities (up to 310 Bq/L) have been measured in wells from the Appalachian Mountains and from the magmatic intrusion of Mont-Saint-Hilaire, known for its high level of indoor radon. The spatial distribution of (222)Rn activity seems to be related mainly to lithology differences between U-richer metasediments of the Appalachian Mountains and magmatic intrusions and the carbonaceous silty shales of the St. Lawrence Platform. Radon is slightly enriched in sodium-chlorine waters that evolved at contact with clay-rich formations. (226)Ra, the parent element of (222)Rn could be easily adsorbed on clays, creating a favorable environment for the production and release of (222)Rn into groundwater. The contribution of groundwater radon to indoor radon or by ingestion is minimal except for specific areas near Mont-Saint-Hilaire or in the Appalachian Mountains where this contribution could reach 45% of the total radioactive annual dose. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Analysis of the 222Rn concentration in argon and a purification technique for gaseous and liquid argon.

    PubMed

    Simgen, H; Zuzel, G

    2009-05-01

    We present an investigation of the (222)Rn concentration in argon with ultra-low background proportional counters. Argon purification tests by means of cryo-adsorption of radon on activated carbon were performed. For gaseous argon the purification process was found to be very efficient. Also in liquid phase the (222)Rn concentration could be reduced significantly, however, the efficiency is lower than in the gas phase. We also have analyzed the initial (222)Rn concentrations in commercial liquid argon. It was found to be significantly higher than in liquid nitrogen.

  2. Surface radioactivity resulting from the deposition of /sup 222/Rn daughter products

    SciTech Connect

    Lively, R.S.; Ney, E.P.

    1987-04-01

    This paper describes the relationship between the /sup 222/Rn in air, and the level of surface radioactivity that results from the build-up and decay of the daughter isotope, /sup 210/Pb. Samples of /sup 222/Rn were collected from Mystery Cave, which is located in southeastern Minnesota and from the basement of a house in Minneapolis, MN. Lead-210 was measured on surfaces within the cave, on a rock removed from the cave, and on a basement window. Surface alpha activities were measured on the rock sample and on the window. Radon-222 concentrations in the cave air ranged from 3 to 13 kBq m-3. In the basement, /sup 222/Rn levels were between 0.2 and 0.4 kBq m-3. Virtually all the surface radioactivity resulted from the deposition and decay of airborne /sup 222/Rn daughter products and was not produced by the decay of U in the rock. Radon-222 concentrations in the cave air were almost 30 times higher than in the basement air; however, the surface /sup 210/Pb activity in the cave was 100 times higher than that in the basement. This suggests that in the cave air, /sup 222/Rn daughter products are more likely to reach the walls and decay to /sup 210/Pb. The measurements of surface alpha activity did not show a similar trend primarily because /sup 210/Pb had diffused further into the coating of dirt on the rock than into the glass of the window. The resulting surface activity of the rock was lower than expected based on the /sup 210/Pb concentration, because many of the alpha-emitting nuclei were at depths beyond the range of emitted alpha particles. On surfaces where the penetration range of alpha particles is greater than the diffusion depth of /sup 210/Pb atoms, either the /sup 210/Pb concentration or surface alpha-activity measurements should provide estimates of average long-term /sup 222/Rn concentrations.

  3. Evaluation of the vertical diffusion coefficients from ERA-40 with 222Rn simulations

    NASA Astrophysics Data System (ADS)

    Olivié, D. J. L.; van Velthoven, P. F. J.; Beljaars, A. C. M.

    2004-08-01

    Boundary layer turbulence has a profound influence on the distribution of tracers with sources or sinks at the surface. The 40-year ERA-40 meteorological data set of the European Centre for Medium-range Weather Forecasts contains archived vertical diffusion coefficients. We evaluated the use of these archived diffusion coefficients instead of off-line diagnosed coefficients based on other meteorological parameters archived during ERA-40 by investigation of the effect on the distribution of the radioactive tracer 222Rn in the chemistry transport model TM3. In total four different sets of vertical diffusion coefficients are compared: (i) 3-hourly vertical diffusion coefficients archived during the ERA-40 project, (ii) 3-hourly off-line diagnosed coefficients from a non-local scheme based on Holtslag and Boville (1993), Vogelezang and Holtslag (1996), and Beljaars and Viterbo (1999), (iii) 6-hourly coefficients archived during the ERA-40 project, and (iv) 6-hourly off-line diagnosed coefficients based on a local scheme described in Louis (1979) and Louis et al. (1982). The diffusion scheme to diagnose the coefficients off-line in (ii) is similar to the diffusion scheme used during the ERA-40 project (i and iii). The archived diffusion coefficients from the ERA-40 project which are time-averaged cause stronger mixing than the instantaneous off-line diagnosed diffusion coefficients. This can be partially attributed to the effect of instantaneous versus time-averaged coefficients, as well as to differences in the diffusion schemes. The 3-hourly off-line diagnosis of diffusion coefficients can reproduce quite well the 3-hourly archived diffusion coefficients. Boundary layer heights are also available for the sets (ii) and (iii). Both were found to be in reasonable agreement with observations of the boundary layer height from Cabauw in the Netherlands and from the FIFE-campaign in the United States. Simulations of 222Rn with the TM3 model using these four sets of vertical

  4. Evaluation of local versus remote areas of CH4 sources at IC3 stations using a combined analysis of 222Rn tracer and Atmospheric Particles Transport Model (APTM) results. Application at the Gredos and Iruelas station (GIC3), Spain.

    NASA Astrophysics Data System (ADS)

    Grossi, Claudia; Morguí, Josep Anton; Curcoll, Roger; Àgueda, Alba; Arnold, Delia; Batet, Oscar; Cañas, Lidia; Nofuentes, Manel; Occhipinti, Paola; Vogel, Felix; Vargas, Arturo; Rodó, Xavier

    2014-05-01

    about 50%. This can be explained taking into consideration that GIC3 station area has high radon exhalation rates according to the literature and the radon uptake from air masses can reach a plateau. On the other hand, CH4 concentrations do not seem to be significantly influenced by IA. The log-log plot between the ratio of normalized and rescaled gases concentrations (CH4/222Rn) and the percentage of the influence of the local area shows a negative linear relation under nocturnal and winter conditions which could depend on the increase of the radon not compensated by the methane increase. Indeed, when the influence of the local area of Gredos and Iruelas station is under the 20% the major methane contribution seems to come from outside the 20x20 km2 IA. Results considering a larger area of interest (up to 80x80 km2) may indicate possible methane sources detected at the GIC3 station.

  5. A practical E-PERM (electret passive environmental radon monitor) system for indoor 222Rn measurement.

    PubMed

    Kotrappa, P; Dempsey, J C; Ramsey, R W; Stieff, L R

    1990-04-01

    The technical and scientific basis for the measurement of indoor 222Rn concentration using an E-PERM (Electret passive environmental radon monitor) has been described in our earlier work. The purpose of this paper is to describe further development of a practical and convenient system that can be used routinely for indoor 222Rn measurement. The ion chamber is now made of electrically conducting plastic to minimize the response from natural gamma radiation. A spring-loaded shutter method is used to cover and uncover the electret from outside the chamber. The electret voltage reader has been modified to improve the accuracy and the ease in operation. The calibration, performance, error analysis, and lower limits of detection for these standardized versions of E-PERMs are also described.

  6. Behavior of the 222Rn daughters on copper surfaces during cleaning

    NASA Astrophysics Data System (ADS)

    Wójcik, Marcin; Zuzel, Grzegorz

    2007-03-01

    Removal of the long-living 222Rn daughters (210Pb, 210Bi and 210Po) from the copper surface has been investigated. Different methods, like chemical etching and electropolishing, were applied to discs exposed earlier to a strong radon source. A long exposure assured effective accumulation of the 222Rn progenies on the copper surface. Cleaning efficiency for 210Pb was tested using a HPGe spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer were used. According to the conducted measurements electropolishing removes very effectively all the isotopes, while etching works only for lead and bismuth, for polonium the cleaning effect is practically negligible. Most probable 210Po is re-deposited on the treated surface.

  7. A biokinetic model for [sup 222]Rn gas distribution and alpha dose in humans following ingestion

    SciTech Connect

    Harley, N.H.; Robbins, E.S. )

    1994-01-01

    A biokinetic model for absorption and distribution of [sup 222]Rn in the body following ingestion in drinking water was developed. The rate parameters for the model are derived from historical human data reported in experiments of Harley et al. (1958) and Hursh et al. (1965). The biokinetic model fits the human data of Hursh et al. well for whole body retention following ingestion of [sup 222]Rn in water on an empty stomach. The equivalent dose to stem cells for stomach and colon cancer is estimated to be 1.6 [times] 10[sup [minus]9] Sv Bq[sup [minus]1]. The model calculations yield 4 and 3 calculated stomach and colon cancers from continuous intake of water at the estimated US average of 5.5 Bq L[sup [minus]1]. 16 refs., 3 figs., 2 tabs.

  8. Behavior of the 222Rn daughters on copper surfaces during cleaning

    SciTech Connect

    Wojcik, Marcin; Zuzel, Grzegorz

    2007-03-28

    Removal of the long-living 222Rn daughters (210Pb, 210Bi and 210Po) from the copper surface has been investigated. Different methods, like chemical etching and electropolishing, were applied to discs exposed earlier to a strong radon source. A long exposure assured effective accumulation of the 222Rn progenies on the copper surface. Cleaning efficiency for 210Pb was tested using a HPGe spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer were used. According to the conducted measurements electropolishing removes very effectively all the isotopes, while etching works only for lead and bismuth, for polonium the cleaning effect is practically negligible. Most probable 210Po is re-deposited on the treated surface.

  9. Measurements of indoor 222RN activity in dwellings and workplaces of Curitiba (Brazil)

    NASA Astrophysics Data System (ADS)

    Corrêa, Janine N.; Paschuk, Sergei A.; Del Claro, Flávia; Kappke, Jaqueline; Perna, Allan F. N.; Schelin, Hugo R.; Denyak, Valeriy

    2014-11-01

    The present work describes the results of systematic measurements of radon (222Rn) in residential environments and workplaces in the Metropolitan Region of Curitiba (Paraná State, Brazil) during the period 2004-2012. For radon in air activity measurements, polycarbonate Track Etch Detectors CR-39, mounted in diffusion chambers protected by borosilicate glass fiber filters, were used. After being exposed in air, the CR-39 detectors were submitted to a chemical etching in a 6.25 M NaOH solution at 70 °C for 14 h. The alpha particle tracks were identified and manually counted with an optical microscope, and with the results of previously performed calibrations, the indoor activity concentration of 222Rn was calculated. The calibration of CR-39 and the alpha particle tracks chemical development procedures were performed in collaboration the National Institute of Radiological Sciences (NIRS, Japan). The major part of indoor 222Rn concentration in residences was found to be below 100 Bq/m3. In the case of working places, all measurements of 222Rn concentrations were below 100 Bq/m3. These values are considered within the limits set by international regulatory agencies, such as the US EPA and ICRP, which adopt up to 148 and 300 Bq/m3 as upper values for the reference levels for radon gas activity in dwellings, respectively. The latest value of 300 Bq/m3 for radon activity in air is proposed by ICRP considering the upper value for the individual dose reference level for radon exposure of 10 mSv/yr.

  10. A new beaded carbon molecular sieve sorbent for 222Rn monitoring.

    PubMed

    Scarpitta, S C

    1996-05-01

    A new commercially available beaded carbon molecular sieve sorbent, Carboxen-564 (20/45 mesh), was tested and compared to Calgon-PCB (40/80) activated carbon for its adsorptive and desorptive characteristics under controlled conditions of temperature (25 degrees C) and relative humidity (RH). The amount of water vapor adsorbed by the beaded carbon molecular sieve material was typically a factor of 4 lower than the activated carbon, with a concomitant fourfold increase in the 222Rn adsorption coefficient, K(Rn). The maximum K(Rn) value for a thin layer of Carboxen-564, following a 2-d exposure at 40% RH, was 7.2 Bq kg(-1) per Bq m(-3). The K(Rn) or a 1-cm bed, following a 2-d exposure was 5.5 Bq m(-3), a 25% reduction. Under dynamic sampling conditions, where 0.4 g of the beaded carbon molecular sieve was contained in a 6 cm x 0.4 cm diameter tube, the maximum K(Rn) value was 6.5 Bq m(-3) after 2.5 h of sampling at 29% RH when the input flow rate was 4.2 x 10(-3) m3 h-1. Kinetic studies were also conducted under passive sampling conditions. The data show that the 222Rn buildup time-constant for a thin layer of the beaded carbon molecular sieve material was 1.3 h, whereas that of a 1 cm bed was 13 h. The 222Rn desorption time-constants, from gram amounts of the beaded carbon molecular sieve material into air and into a commercially available toluene based liquid scintillation cocktail, were 2 h and 3 h, respectively. Carboxen's high 222Rn adsorbing capacity, rapid kinetics, hydrophobicity and physical properties makes it an attractive alternative to other commercially available activated carbon used in passive and dynamic sampling devices.

  11. Measurements of 222Rn activity concentration in domestic water sources in Penang, northern peninsular Malaysia.

    PubMed

    Muhammad, B G; Jaafar, M S; Azhar, A R; Akpa, T C

    2012-04-01

    Measurements of (222)Rn activity concentration were carried out in 39 samples collected from the domestic and drinking water sources used in the island and mainland of Penang, northern peninsular, Malaysia. The measured activity concentrations ranged from 7.49 to 26.25 Bq l(-1), 0.49 to 9.72 Bq l(-1) and 0.58 to 2.54 Bq l(-1) in the raw, treated and bottled water samples collected, respectively. This indicated relatively high radon concentrations compared with that from other parts of the world, which still falls below the WHO recommended treatment level of 100 Bq l(-1). From this data, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn resulting from 1 y's consumption of these water were estimated to range from 0.003 to 0.048, 0.001 to 0.018 and 0.002 to 0.023 mSv y(-1), for age groups 0-1, 2-16 and >16 y, respectively.

  12. (222)Rn, (220)Rn and other dissolved gases in mineral waters of southeast Brazil.

    PubMed

    Bonotto, Daniel Marcos

    2014-06-01

    This paper describes the natural radioactivity due to (222)Rn and (220)Rn in mineral waters occurring at São Paulo and Minas Gerais states, Brazil, that are extensively used for drinking in public places, bottling and bathing purposes, among other. The measurements of these alpha-emitting radionuclides were also accompanied by the monitoring of temperature and some dissolved gases (O2, CO2 and H2S) in 75 water sources located in 14 municipalities of those states. Eight water sources yielded (220)Rn activity concentration values below the detection limit of 4 mBq/L. On other hand, (222)Rn activity concentration values exceeding the WHO guidance level of 100 Bq/L in drinking-water for public water supplies were found in two springs, named Villela and Dona Beja, whose discharge occurs in areas characterized by the presence of enhanced levels of natural radioelements in rocks. The obtained results were compared with the guidelines of the Brazilian Code of Mineral Waters (BCMW) that was established in 1945 and is still in force in the country. The (222)Rn and (220)Rn activity concentration data allowed perform dose radiation calculations based on the potential alpha energy concentration (PAEC), whose implications for health risk have been also considered in this paper. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. {sup 222}Rn as an indicator of nonaqueous phase liquid contamination in groundwater

    SciTech Connect

    Cantaloub, M.G.; Higginbotham, J.F.; Gottipati, S.

    1996-06-01

    There is considerable interest in the detection and monitoring of Nonaqueous Phase Liquids (NAPLs), particularly as it relates to groundwater protection and remediation. The measurement of NAPLs becomes increasingly difficult as they approach residual saturation levels within a contaminated aquifer. Results from field and modeling studies have demonstrated that naturally occurring {sup 222}Rn can be used to identify and quantify residual NAPLs in saturated and unsaturated aquifer media. The method relies on the high solubility and partitioning of radon into organic materials. Radon partitioning into residual NAPL results in a relative radon deficit in the pore water within the contaminated matrix. Initial work utilized scintillation cells for measuring {sup 222}Rn and its alpha emitting progeny. The current work has incorporated extractive liquid scintillation and pulse shape analysis in an effort to process larger sample numbers while maintaining a detection level comparable to that of the scintillation cell method. Laboratory studies were conducted on columns in various states of saturation and with various levels of NAPL contamination. The results suggest that the relative depletion of {sup 222}Rn in water originating from regions of NAPL contamination might be a useful field method for confirming the presence of NAPLs and has the potential as an indicator of remediation success.

  14. 222Rn Measurements at Federal University of Technology (UTFPR, Curitiba, PR, Brazil)

    NASA Astrophysics Data System (ADS)

    Corrêa, Janine Nicolosi; Paschuk, Sergei A.; Fior, Loriane; Schelin, Hugo R.; da Silva, Ruben D. Flores; Pöttker, Fabiana; de Paula Melo, Vicente

    2008-08-01

    Numerous studies and reports indicate that the indoor radon inhalation by humans has to be considered as the main source of radiological hazard and probably the second most important cause of lung cancer after that of smoking. During the last decades, many countries have put considerable efforts into direct measurements and monitoring of 222Rn and its progeny exposure, as well as 222Rn concentration mapping. Present measurements were performed with an aim to study possible correlation between used construction materials and 222Rn indoor concentration levels. For this purpose, 50 Lexan track detectors were exposed in the air (indoor as well as outdoor) during two months (June and July) within the central region of Curitiba and Campo Largo (Parana St., Brazil). Since this period of the year is usually rather cold in the South of Brazil, exposition time was chosen to prevent possible saturation of alpha tracks. The second step of measurements was performed during the months of November, December and January, when 50 Lexan track detectors were exposed in the air (indoor and outdoor) within the same urban area. Achieved results are being compared with other experimental data.

  15. {sup 222}Rn Measurements at Federal University of Technology (UTFPR, Curitiba, PR, Brazil)

    SciTech Connect

    Correa, Janine Nicolosi; Paschuk, Sergei A.; Fior, Loriane; Schelin, Hugo R.; Flores da Silva, Ruben D.; Poettker, Fabiana; Paula Melo, Vicente de

    2008-08-07

    Numerous studies and reports indicate that the indoor radon inhalation by humans has to be considered as the main source of radiological hazard and probably the second most important cause of lung cancer after that of smoking. During the last decades, many countries have put considerable efforts into direct measurements and monitoring of {sup 222}Rn and its progeny exposure, as well as {sup 222}Rn concentration mapping. Present measurements were performed with an aim to study possible correlation between used construction materials and {sup 222}Rn indoor concentration levels. For this purpose, 50 Lexan track detectors were exposed in the air (indoor as well as outdoor) during two months (June and July) within the central region of Curitiba and Campo Largo (Parana St., Brazil). Since this period of the year is usually rather cold in the South of Brazil, exposition time was chosen to prevent possible saturation of alpha tracks. The second step of measurements was performed during the months of November, December and January, when 50 Lexan track detectors were exposed in the air (indoor and outdoor) within the same urban area. Achieved results are being compared with other experimental data.

  16. Occurrence of 222Rn in irrigation water from Wadi Al-Rummah Qassim province, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    El-Taher, Atef; Alashrah, Saleh

    2015-08-01

    Naturally accruing radioactive materials in the environment have received attention since they may be present in high level and pose risk to human health. The present work deals with measuring of 222Rn in irrigation water samples from Wadi Al-Rummah, Qassim province, in central of Saudi Arabia. 222Rn concentrations were measured by RAD7. It was found that the concentration of 222Rn ranged from 2.1 ± 1.2 to 7.2 ± 1.5 BqL-1. These values are below 11.1 BqL-1 the maximum contamination level recommended from the U.S. Environmental Protection Agency. The calculated annual effective dose (AED) ranging from 7.5 to 26.1 µSv/y. It was evident that the total annual effective dose resulting from radon in irrigation groundwater in Wadi Al-Rummah in Qassim area were significantly lower than the recommended limit 1 mSv/y for the public.

  17. Radon exhalation rates and gamma doses from ceramic tiles.

    PubMed

    O'Brien, R S; Aral, H; Peggie, J R

    1998-12-01

    This study was carried out to assess the possible radiological hazard resulting from the use of zircon in glaze applied to tiles used in buildings. The 226Ra content of various stains and glazing compounds was measured using gamma spectroscopy and the 222Rn exhalation rates for these materials were measured using adsorption on activated charcoal. The radon exhalation rates were found to be close to or less than the minimum detectable values for the equipment used. This limit was much lower than the estimated exhalation rates, which were calculated assuming that the parameters controlling the emanation and diffusion of 222Rn in the materials studied were similar to those of soil. This implied that the 222Rn emanation coefficients and/or diffusion coefficients for most of the materials studied were very much lower than expected. Measurements on zircon powders showed that the 222Rn emanation coefficient for zircon was much lower than that for soil, indicating that only a small fraction of the 222Rn produced by the decay of 226Ra was able to escape from the zircon grains. The estimated increase in radon concentration in room air and the estimated external gamma radiation dose resulting from the use of zircon glaze are both much lower than the relevant action level and dose limit.

  18. On the Correction of Spatial and Statistical Uncertainties in Systematic Measurements of 222Rn for Earthquake Prediction

    NASA Astrophysics Data System (ADS)

    Külahcı, Fatih; Şen, Zekâi

    2013-12-01

    In earthquake prediction studies, the regional behaviour of accurate 222Rn measurements at a set of sites plays a significant role. Here, measurements are obtained using active and passive radon detector systems in an earthquake-active region of Turkey. Two new methods are proposed to explain the spatial behaviours and the statistical uncertainties in the 222Rn emission measurements along fault lines in relation to earthquake occurrence. The absolute point cumulative semivariogram (APCSV) and perturbation method (PM) help to depict the spatial distribution patterns of 222Rn in addition to the joint effects of the K dr, the radon distribution coefficient, and the perturbation radon distribution coefficient (PRDC). The K dr coefficient assists in identifying the spatial distributional behaviour in 222Rn concentrations and their migration along the Earth's surface layers. The PRDC considers not only the arithmetic averages but also the variances (or standard deviations) and the correlation coefficients, in addition to the size of the error among the 222Rn measurements. The applications of these methodologies are performed for 13,000 222Rn measurements that are deemed to be sufficient for the characterization of tectonics in the Keban Reservoir along the East Anatolian Fault System (EAFS) in Turkey. The results are evaluated for the İçme earthquake (M L 5.4, 5.7 km, 23 June 2011), which occurred in the vicinity of the EAFS.

  19. A new beaded carbon molecular sieve sorbent for {sup 222}Rn monitoring

    SciTech Connect

    Scarpitta, S.C.

    1996-05-01

    A new commercially available beaded carbon molecular sieve sorbent, Carboxen-564 (20/45 mesh), was tested and compared to Calgon-PCB (40/80) activated carbon for its adsorptive and desorptive characteristics under controlled conditions of temperature (25{degrees})C and relative humidity (RH). The amount of water vapor adsorbed by the beaded carbon molecular sieve material was typically a factor of 4 lower than the activated carbon, with a concomitant fourfold increase in the {sup 222}Rn adsorption coefficient, K{sub Rn}. The maximum K{sub Rn} value for a thin layer of Carboxen-564, following a 2-d exposure at 40% RH, was 7.2 Bq kg{sup {minus}1} per Bq m{sup {minus}3}. The K{sub Rn} for a 1-cm bed, following a 2-d exposure was 5.5 Bq m{sup {minus}3}, a 25% reduction. under dynamic sampling conditions, where 0.4 g of the beaded carbon molecular sieve was contained in a 6 cm x 0.4 cm diameter tube, the maximum K{sub Rn} value was 6.5 Bq m{sup {minus}3} after 2.5 h of sampling at 29% RH when the input flow rate was 4.2 x 10{sup {minus}3} m{sup 3} h{sup {minus}1}. Kinetic studies were also conducted under passive sampling conditions. The data show that the {sup 222}Rn buildup time-constant for a thin layer of the beaded carbon molecular sieve material was 1.3 h, whereas that of a 1 cm bed was 13 h. The {sup 222}Rn desorption time-constants, from gram amounts of the beaded carbon molecular sieve material was 1.3 h, whereas that of a 1 cm bed was 13 h. The {sup 222}Rn desorption time-constants, from gram amounts of the beaded carbon molecular sieve material into air and into a commercially available toluene based liquid scintillation cocktail, were 2 h and 3 h, respectively. Carboxen`s high {sup 222}Rn adsorbing capacity, rapid kinetics, hydrophobicity and physical properties makes it an attractive alternative to other commercially available activated carbon used in passive and dynamic sampling devices. 18 refs., 7 figs.

  20. Estuarine geochemistry of /sup 224/Ra, /sup 226/Ra, and /sup 222/Rn

    SciTech Connect

    Elsinger, R.J.

    1982-01-01

    Desorption from river borne sediments is the most likely source of the excess /sup 226/Ra. Laboratory mixing experiments on Pee Dee River sediments show an increase in /sup 226/Ra desorption with increasing salinities with maximum desorption occurring at or above 20/sup 0//oo salinity. Desorption and diffusion are the sources for /sup 226/Ra in the estuarine systems. In Winyah Bay the /sup 228/Ra//sup 226/Ra activity ratio does not change significantly with salinity, averaging around 1.4, indicating desorption as the major source of /sup 228/Ra. In the Yangtze River the /sup 228/Ra//sup 226/Ra activity ratio is constant (approx.1.90) until increasing linearly above 16/sup 0//oo. A diffusive flux from regeneration by /sup 232/Th decay in shelf sediments is the source of the increase. In Delaware Bay /sup 228/Ra increases faster than /sup 226/Ra in the less than or equal to22/sup 0//oo water, indicating a source in addition to desorption. The increase can be balanced by a 0.33 dpm/cm/sup 2/-year flux over the upper part of the Bay where fine grained sediments predominate. /sup 224/Ra behavior is controlled by its 3.64 day half-life. In Winyah Bay a flux of around 0.4 dpm/cm/sup 2/-day is necessary to support the standing crop of non-desorbed /sup 224/Ra in the water column. In Delaware Bay the nearly constant /sup 224/Ra in concentration over the 2.5/sup 0//oo to 12/sup 0//oo salinity range are maintained by regeneration from /sup 228/Th in the turbidity maximum zones and diffusion from bottom sediments. Water leaving on ebb tide from a salt marsh on Delaware Bay had increases in all three radium isotopes (/sup 224/Ra > /sup 228/Ra > /sup 226/Ra) compared to water coming in on the flood tide. Excess /sup 222/Rn concentrations in a fresh water section of the Pee Dee River show a decreasing downstream gradient. Using these gradients to determine evasion rates, stagnant film thicknesses range from 21..mu.. to 62..mu...

  1. Use of 222Rn as a natural tracer to evaluate the efficiency of flushing test at DNAPL contaminated area

    NASA Astrophysics Data System (ADS)

    Lee, S.; Joun, W.; Kim, H.; Kaown, D.; Lee, K.

    2013-12-01

    Flushing test was applied to remediate the depth-discrete residual dense non-aqueous phase liquid (DNAPL) sources in an unsaturated zone at an industrial complex in Wonju, Korea. Remediation efficiency for flushing test was evaluated by comparing the natural tracer 222Rn concentration data in groundwater and the mass discharges of trichloroethylene (TCE) through a cross section before and during the test period. In the previous research performed at the study site, the location of residual DNAPL sources in the unsaturated zone was identified using the natural tracer 222Rn and contaminant concentrations based on the information for characteristics of radon which was partitioning into TCE. The natural injection method and pressurized injection method were applied for water injection. Uncontaminated groundwater around main source area was used as injection water. Temporal and spatial monitoring results show that a combined water injection (conducting both natural injection and pressurization injection) is an effective operation method. The 222Rn activities and TCE concentrations in groundwater fluctuated irregularly with water level increase at the main source area. The natural tracer 222Rn in groundwater originating from the underlying crystalline biotite granite, had a wide range from 15,000 to 183,000 Bq/m3 and total concentrations of TCE ranged from 0.03 to 1.79 mg/l. These temporal variations in 222Rn activities might be caused by not only the unknown quantities of residual TCE in the unsaturated zone but also the characteristics of radon partitioning into residual TCE with water level increase. From these results, the 222Rn activities could not be used directly as a natural tracer to evaluate the remediation efficiency due to the irregular production. Therefore, for more precise efficiency evaluation, the comparative analysis between 222Rn activities and relative contaminant concentrations data is required.

  2. Investigating hydrologic controls on glacier velocity using 222Rn as a proxy for variable subglacial pressure

    NASA Astrophysics Data System (ADS)

    Linhoff, B.; Charette, M. A.; Tedstone, A. J.; Ingle, A.; Bartholomew, I.; Cowton, T.; Butler, C. E.; Sole, A. J.; Nienow, P. W.; Wadham, J. L.; Chandler, D.

    2013-12-01

    Each summer, meltwater forms on the surface of the Greenland Ice Sheet and travels through cracks and moulins to the ice-bed. There, hydraulic pressure in cavities and channels controls glacial sliding; coincident with the highest hydraulic pressures are the fastest annual glacial speeds. Meltwater pathways at the ice-bed undergo a seasonal evolution from high-pressure, inefficient linked-cavity systems at the onset of spring melt to low-pressure, high-capacity channelized systems by midsummer. Radon-222 (t1/2 = 3.8 days) is a promising new tool for glaciology (Bhatia et al., 2011) as it is injected into meltwater during interaction with sediment and rock through the radioactive decay of naturally occurring 226Ra. Therefore in proglacial rivers, 222Rn can be assumed to trace fluxes of subglacial groundwater or meltwater transiently stored at the ice-bed. Radon-222 was quantified in the proglacial river of Leverett Glacier, a large outlet glacier of the Greenland Ice Sheet, during the summers of 2011 (May 8th - August 10th) and 2012 (May 12th - August 1st). Continuous (hourly) measurements were made using a RAD-7 (Durridge Inc.) with gas-permeable tubing in place of the air-water equilibrator. We estimated englacial meltwater storage as the difference between proglacial river discharge and meltwater inputs, calculated from a positive degree-day melt model based on temperature sensors on the ice surface and MODIS satellite imagery to determine the timing and size of supraglacial lake drainage events. Periods of high glacial velocity displayed strong subdiurnal covariations with 222Rn. We hypothesize that this is the result of increasing englacial meltwater storage, channel pressurization and 222Rn tracing groundwater fluxes. When pressure is rising in channels, meltwater is driven distally into adjacent linked cavity networks where it is temporarily stored while channel pressures are centrifugal. During these periods, meltwater traveling though channels likely has

  3. An improved sup 222 Rn canister using a two-stage charcoal system

    SciTech Connect

    Scarpitta, S.C.; Harley, N.H. )

    1991-02-01

    A prototype for an improved passive {sup 222}Rn canister (R-Canister) was designed and compared to conventional charcoal canisters for its adsorptive and desorptive characteristics following exposures to {sup 222}Rn at 23{degrees}C in the presence of water vapor. The R-Canister, containing a two-stage charcoal system, minimizes the adverse effects of water vapor by maintaining the amount of adsorbed water vapor in the primary Rn adsorbent below the break-point of the charcoal. This is achieved by the placement of a desiccant charcoal cartridge 6 cm above the primary Rn adsorbent. The optimal bed depth of the primary adsorbent, determined from a diffusion study, was found to be 2.3 cm. The measured value for the effective diffusion coefficient of RN in a peat-based charcoal at 15% humidity and 25{degrees}C is 7.97 x 10(-10) m2 s-1. Exposures to 70% humidity for 7 d increased the buildup time-constant of Rn in the R-Canisters by 33% as compared to R-Canisters exposed to 15% humidity. At relative humidities ranging from 15-70%, the {sup 222}Rn buildup time-constant of the R-Canister ranged from 43-94 h, whereas the desorption time-constant ranged from 46-64 h. Typical buildup time-constants and desorption time-constants for conventional fully-opened charcoal canisters currently in field use ranged from 30-43 h and 17-29 h, respectively, over the same range of humidities.

  4. Radon-222, sup 222 Rn progeny, and sup 220 Rn progeny levels in 70 houses

    SciTech Connect

    Dudney, C.S.; Hawthorne, A.R.; Wallace, R.G.; Reed, R.P. )

    1990-03-01

    A year-long, multipollutant, indoor air quality study involving 70 occupied houses in four states was completed in 1987. All of the houses included in the study had a partial or complete basement with a concrete slab floor and block walls. On an approximately quarterly schedule, integrating monitors for short-lived Rn progeny, nitrogen dioxide, formaldehyde, and water vapor were exposed for 1 wk in each house on both the basement and main floors. At the beginning of the study, a pair of alpha-track detectors were placed on top of the refrigerator in the kitchen (or some other sampling location on the main floor) and at a location in the basement. One detector at each location was left in place for a year while the other detector was retrieved and replaced once every 3-mo period. In addition, short-term measurements of Rn and {sup 222}Rn progeny were made at all sampling locations once per quarter. In this study, comparisons were made between: (1) seasonal and annual averages, (2) summer and winter averages, (3) living-area and basement results, (4) {sup 222}Rn and {sup 220}Rn progeny, and (5) short- and long-term measurements. The Rn and Rn progeny concentrations in houses near Huntsville, AL were found to be well above recommended action levels (150 Bq m-3). For houses near Birmingham, AL, summer Rn concentrations were found to exceed winter concentrations, whereas for the other houses in the study, winter concentrations exceeded summer concentrations. Potential alpha energy concentrations (PAEC) from {sup 220}Rn progeny were found to be generally less than PAEC from {sup 222}Rn.

  5. Radon-222, 222Rn progeny, and 220Rn progeny levels in 70 houses.

    PubMed

    Dudney, C S; Hawthorne, A R; Wallace, R G; Reed, R P

    1990-03-01

    A year-long, multipollutant, indoor air quality study involving 70 occupied houses in four states was completed in 1987. All of the houses included in the study had a partial or complete basement with a concrete slab floor and block walls. On an approximately quarterly schedule, integrating monitors for short-lived Rn progeny, nitrogen dioxide, formaldehyde, and water vapor were exposed for 1 wk in each house on both the basement and main floors. At the beginning of the study, a pair of alpha-track detectors were placed on top of the refrigerator in the kitchen (or some other sampling location on the main floor) and at a location in the basement. One detector at each location was left in place for a year while the other detector was retrieved and replaced once every 3-mo period. In addition, short-term measurements of Rn and 222Rn progeny were made at all sampling locations once per quarter. In this study, comparisons were made between: (1) seasonal and annual averages, (2) summer and winter averages, (3) living-area and basement results, (4) 222Rn and 220Rn progeny, and (5) short- and long-term measurements. The Rn and Rn progeny concentrations in houses near Huntsville, AL were found to be well above recommended action levels (150 Bq m-3). For houses near Birmingham, AL, summer Rn concentrations were found to exceed winter concentrations, whereas for the other houses in the study, winter concentrations exceeded summer concentrations. Potential alpha energy concentrations (PAEC) from 220Rn progeny were found to be generally less than PAEC from 222Rn.

  6. Removal of the long-lived {sup 222}Rn daughters from steel and germanium surfaces

    SciTech Connect

    Wojcik, Marcin; Zuzel, Grzegorz; Majorovits, Bela

    2011-04-27

    Removal of the long-lived {sup 222}Rn daughters ({sup 210}Pb, {sup 210}Bi and {sup 210}Po) from stainless steel and germanium surfaces was investigated. As cleaning technique etching was applied to samples in a form of discs exposed earlier to a strong radon source. Reduction of the {sup 210}Pb activity was tested using a HPGe spectrometer, for {sup 210}Bi a beta spectrometer and for {sup 210}Po an alpha spectrometer was used. According to the conducted measurements all the isotopes were removed very efficiently from germanium. Results obtained for stainless steel were worse but still better than those achieved for copper.

  7. The development of a 222Rn standard solution dispenser at NPL.

    PubMed

    Dean, J C J; Kolkowski, P

    2004-01-01

    The design, operation and performance of a unit for dispensing standardised aqueous solutions of 222Rn is described. The unit consists of a sealed polyethylene capsule (containing a known weight of a 226Ra standard solution) immersed in water inside a cylindrical stainless-steel accumulation chamber. The chamber is fitted with valves at each end and has a central bellows so that the chamber can be compressed to dispense solution. The degree of compression, and thus the weight of solution dispensed, is controlled by a microprocessor-controlled motor-drive mechanism. The solution is dispensed via a needle positioned beneath the lower valve.

  8. Long-term temporal variability of the radon-222 exhalation flux from a landform covered by low uranium grade waste rock.

    PubMed

    Bollhöfer, Andreas; Doering, Che

    2016-01-01

    Radon-222 exhalation flux densities from two different substrates of several metres thickness, waste rock and waste rock mixed with approximately 30% lateritic material, were measured over a period of five years in the wet-dry tropics of Northern Australia. Fourteen measurement campaigns using activated charcoal canisters (n > 1000) covered both dry and wet seasons and showed differences in seasonal and long term trends of the (222)Rn exhalation flux densities normalised to the (226)Ra activity concentrations of the substrate. Dry season (222)Rn exhalation was generally higher for the mixed substrate, due to the larger fraction of fines. Seasonality established within the first year of landform construction on the mixed substrate, due to the higher water holding capacity of the lateritic material. In contrast, waste rock only shows no seasonality until years four and five after construction, when average normalised dry season (222)Rn exhalation flux densities from waste rock increase to values (0.47 ± 0.06 mBq m(-2) s(-1) per Bq kg(-1)) similar to the mixed substrate (0.64 ± 0.08 mBq m(-2) s(-1) per Bq kg(-1)), likely due to an increase in fines from rapid weathering of the schistose waste rock. Volumetric water content has been used to parametrize relative (222)Rn exhalation and we determined that wet season (222)Rn exhalation is about 40% of the dry season exhalation.

  9. Measurement of 222Rn dissolved in water at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Blevis, I.; Boger, J.; Bonvin, E.; Cleveland, B. T.; Dai, X.; Dalnoki-Veress, F.; Doucas, G.; Farine, J.; Fergani, H.; Grant, D.; Hahn, R. L.; Hamer, A. S.; Hargrove, C. K.; Heron, H.; Jagam, P.; Jelley, N. A.; Jillings, C.; Knox, A. B.; Lee, H. W.; Levine, I.; Liu, M.; Majerus, S.; McDonald, A.; McFarlane, K.; Mifflin, C.; Noble, A. J.; Noël, S.; Novikov, V. M.; Rowley, J. K.; Shatkay, M.; Simpson, J. J.; Sinclair, D.; Sur, B.; Wang, J.-X.; Yeh, M.; Zhu, X.

    2004-01-01

    The technique used at the Sudbury Neutrino Observatory (SNO) to measure the concentration of 222Rn in water is described. Water from the SNO detector is passed through a vacuum degasser (in the light water system) or a membrane contact degasser (in the heavy water system) where dissolved gases, including radon, are liberated. The degasser is connected to a vacuum system which collects the radon on a cold trap and removes most other gases, such as water vapor and N 2. After roughly 0.5 tonnes of H 2O or 6 tonnes of D 2O have been sampled, the accumulated radon is transferred to a Lucas cell. The cell is mounted on a photomultiplier tube which detects the α-particles from the decay of 222Rn and its progeny. The overall degassing and concentration efficiency is about 38% and the single-α counting efficiency is approximately 75%. The sensitivity of the radon assay system for D 2O is equivalent to ˜3×10 -15 g U/g water. The radon concentration in both the H 2O and D 2O is sufficiently low that the rate of background events from U-chain elements is a small fraction of the interaction rate of solar neutrinos by the neutral current reaction.

  10. Exposures to 222Rn from consumption of underground municipal water supplies in Pakistan.

    PubMed

    Manzoor, F; Alaamer, A S; Tahir, S N A

    2008-01-01

    This paper presents the results of radon ((222)Rn) concentration measurements in municipal supply drinking water in metropolitan Lahore city of Pakistan and evaluation of consequent radiological effects. In this respect, water samples were collected in all nine municipal towns of Lahore city and analysed employing a high-resolution gamma spectrometric system. Radon concentration varied from 2.0 +/- 0.3 to 7.9 +/- 2.1 Bq l(-1). Mean value of annual effective dose for an individual consumer was assessed to be 16.5 +/- 12.8 microSv y(-1). (222)Rn mean concentration measured in this study is comparable with the reported values for drinking water determined worldwide and found to be less than the limit of 100 Bq l(-1) recommended by the World Health Organisation for public water supplies. The results of this study may be helpful in establishing background levels of radon in drinking water that could be used not only to distinguish additional contributions when a contamination event occurs but also to implement water quality standards by the concerned authorities to maintain radioactive contamination free drinking water supplies for the population.

  11. (The determination of sup 222 Rn flux from soils based on sup 210 Pb and sup 226 Ra disequilibrium)

    SciTech Connect

    Turekian, K.K.

    1991-01-01

    The emanating fraction of radon in soils from the southern part of the United States is about 40% greater than in those from the northern part. The mean {sup 226}Ra activity in the southern soils is also slightly higher and as a consequence the {sup 222}Rn flux derived from the top 50 cm. is greater in the southern samples. We tentatively attribute these observations to the greater degree of weathering associated with the pre-glacial age of the parent material of many of the southern soils. The weathering has concentrated {sup 226}Ra near grain surfaces and results in an increased emanating power for {sup 222}Rn. The estimated correction in {sup 210}Pb analyses described above results in a small decrease in our estimate of the mean loss rate of {sup 222}Rn from the upper 50 cm of soils.

  12. Examining Submarine Ground-Water Discharge into Florida Bay by using 222Rn and Continuous Resistivity Profiling

    USGS Publications Warehouse

    Swarzenski, Peter; Reich, Chris; Rudnick, David

    2009-01-01

    Estimates of submarine ground-water discharge (SGD) into Florida Bay remain one of the least understood components of a regional water balance. To quantify the magnitude and seasonality of SGD into upper Florida Bay, research activities included the use of the natural geochemical tracer, 222Rn, to examine potential SGD hotspots (222Rn surveys) and to quantify the total (saline + fresh water component) SGD rates at select sites (222Rn time-series). To obtain a synoptic map of the 222Rn distribution within our study site in Florida Bay, we set up a flow-through system on a small boat that consisted of a Differential Global Positioning System, a calibrated YSI, Inc CTD sensor with a sampling rate of 0.5 min, and a submersible pump (z = 0.5 m) that continuously fed water into an air/water exchanger that was plumbed simultaneously into four RAD7 222Rn air monitors. To obtain local advective ground-water flux estimates, 222Rn time-series experiments were deployed at strategic positions across hydrologic and geologic gradients within our study site. These time-series stations consisted of a submersible pump, a Solinist DIVER (to record continuous CTD parameters) and two RAD7 222Rn air monitors plumbed into an air/water exchanger. Repeat time-series 222Rn measurements were conducted for 3-4 days across several tidal excursions. Radon was also measured in the air during each sampling campaign by a dedicated RAD7. We obtained ground-water discharge information by calculating a 222Rn mass balance that accounted for lateral and horizontal exchange, as well as an appropriate ground-water 222Rn end member activity. Another research component utilized marine continuous resistivity profiling (CRP) surveys to examine the subsurface salinity structure within Florida Bay sediments. This system consisted of an AGI SuperSting 8 channel receiver attached to a streamer cable that had two current (A,B) electrodes and nine potential electrodes that were spaced 10 m apart. A separate DGPS

  13. Exploring (222)Rn as a tool for tracing groundwater inflows from eskers and moraines into slope peatlands of the Amos region of Quebec, Canada.

    PubMed

    Berthot, Laureline; Pinti, Daniele L; Larocque, Marie; Gagné, Sylvain; Ferlatte, Miryane; Cloutier, Vincent

    2016-11-01

    Peatlands can play an important role in the hydrological dynamics of a watershed. However, interactions between groundwater and peat water remain poorly understood. Here, we present results of an exploratory study destined to test radon ((222)Rn) as a potential tracer of groundwater inflows from fluvioglacial landform aquifers to slope peatlands in the Amos region of Quebec, Canada. (222)Rn occurs in groundwater but is expected to be absent from peat water because of its rapid degassing to the atmosphere. Any (222)Rn activity detected in peat water should therefore derive from groundwater inflow. (222)Rn activity was measured in groundwater from municipal, domestic wells and newly drilled and instrumented piezometers from the Saint-Mathieu-Berry and Barraute eskers (n = 9), from the Harricana Moraine (n = 4), and from the fractured bedrock (n = 3). Forty measurements of (222)Rn activity were made from piezometers installed in five slope peatlands, along six transects oriented perpendicular to the fluvioglacial deposits. The relationship between (222)Rn and total dissolved solids (TDS) measured in water from the mineral deposits underlying the peat layer suggests that (222)Rn is introduced by lateral inflow from eskers and moraine together with salinity. This input is then diluted by peat water, depleted in both TDS and (222)Rn. The fact that a relationship between TDS and (222)Rn is visible calls for a continuous inflow of groundwater from lateral eskers/moraines, being (222)Rn rapidly removed from the system by radioactive decay. Although more research is required to improve the sampling and tracing techniques, this work shows the potential of (222)Rn tracer to identify groundwater inflow areas from granular aquifers found in eskers and moraines to slope peatlands. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Attached, unattached fraction of progeny concentrations and equilibrium factor for dose assessments from (222)Rn and (220)Rn.

    PubMed

    Singh, Parminder; Saini, Komal; Mishra, Rosaline; Sahoo, Bijay Kumar; Bajwa, Bikramjit Singh

    2016-08-01

    In this study, measurements of indoor radon ((222)Rn), thoron ((220)Rn) and their equilibrium equivalent concentration (EEC) were carried out in 96 dwellings from 22 different villages situated in Hamirpur district, Himachal Pradesh, India, by using LR-115 type II-based pinhole twin cup dosimeters and deposition-based progeny sensors (DRPS/DTPS). The annual average indoor (222)Rn and (220)Rn concentrations observed in these dwellings were 63.82 and 89.59 Bq/m(3), respectively, while the average EEC (attached + unattached) for (222)Rn and (220)Rn was 29.28 and 2.74 Bq/m(3). For (222)Rn (f Rn) and (220)Rn (f Tn), the average values of unattached fraction were 0.11 and 0.09, respectively. The equilibrium factors for radon (F Rn) and thoron (F Tn) varied from 0.12 to 0.77 with an average of 0.50, and from 0.01 to 0.34 with an average of 0.05, respectively. The annual inhalation dose due to mouth and nasal breathing was calculated using dose conversion factors and unattached fractions. The indoor annual effective doses for (222)Rn (AEDR) and (220)Rn (AEDT) were found to be 1.92 and 0.83 mSv a(-1), respectively. The values of (222)Rn/(220)Rn concentrations and annual effective doses obtained in the present study are within the safe limits as recommended by the International Commission on Radiological Protection for indoor dwelling exposure conditions.

  15. Estimation of Radiological Dose From Progeny of 222Rn and 220Rn Using DTPS/DRPS and Wire-Mesh-Capped Progeny Sensors

    PubMed Central

    Jakhu, Rajan; Bangotra, Pargin; Mittal, Harish Mohan

    2016-01-01

    Radon (222Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of unattached and attached short-lived 222Rn and thoron (220Rn) progeny in indoor environment of some dwellings of the Jalandhar and Kapurthala districts of Punjab had been calculated using the deposition-based progeny sensors (DRPS/DTPS) and wire-mesh-capped (DRPS/DTPS) progeny sensors. The observed concentration of attached 222Rn and 220Rn progeny showed the variation from 5 to 21 Bq·m−3 and 0.3 to 1.7 Bq·m−3, respectively. The activity concentration of the unattached 222Rn and 220Rn progeny varies from 1 to 5 Bq·m−3 and 0.1 to 0.6 Bq·m−3, respectively. The average unattached fraction of 222Rn and 220Rn progeny is 0.2 and 0.1. The average value of the indoor aerosol concentration attachment rate of 222Rn and 220Rn progeny is 2251 cm−3, 24 ms−1, and 617 ms−1. Relation among the unattached fraction and attachment rate is established, and the obtained results of dose conversion factors show the significance of the nano-sized 222Rn decay products in 222Rn dosimetry. PMID:27994523

  16. Estimation of Radiological Dose From Progeny of (222)Rn and (220)Rn Using DTPS/DRPS and Wire-Mesh-Capped Progeny Sensors.

    PubMed

    Mehra, Rohit; Jakhu, Rajan; Bangotra, Pargin; Mittal, Harish Mohan

    2016-01-01

    Radon ((222)Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of unattached and attached short-lived (222)Rn and thoron ((220)Rn) progeny in indoor environment of some dwellings of the Jalandhar and Kapurthala districts of Punjab had been calculated using the deposition-based progeny sensors (DRPS/DTPS) and wire-mesh-capped (DRPS/DTPS) progeny sensors. The observed concentration of attached (222)Rn and (220)Rn progeny showed the variation from 5 to 21 Bq·m(-3) and 0.3 to 1.7 Bq·m(-3), respectively. The activity concentration of the unattached (222)Rn and (220)Rn progeny varies from 1 to 5 Bq·m(-3) and 0.1 to 0.6 Bq·m(-3), respectively. The average unattached fraction of (222)Rn and (220)Rn progeny is 0.2 and 0.1. The average value of the indoor aerosol concentration attachment rate of (222)Rn and (220)Rn progeny is 2251 cm(-3), 24 ms(-1), and 617 ms(-1). Relation among the unattached fraction and attachment rate is established, and the obtained results of dose conversion factors show the significance of the nano-sized (222)Rn decay products in (222)Rn dosimetry.

  17. Radon-222 exhalation from open ground on and around a uranium mine in the wet-dry tropics.

    PubMed

    Lawrence, Cameron E; Akber, Riaz A; Bollhöfer, Andreas; Martin, Paul

    2009-01-01

    Radon-222 exhalation from the ground surface depends upon a number of variables such as the 226Ra activity concentration and its distribution in soil grains; soil grain size; soil porosity, temperature and moisture; atmospheric pressure, rainfall and temperature. In this study, 222Rn exhalation flux density measurements within and around the Ranger uranium mine in northern Australia were performed to investigate the effect of these variables within a tropical region. Measurements were taken at the waste rock dumps, ore stockpiles, mine pits, and at sites where effluent water with elevated 226Ra concentration has been spray irrigated over land, as well as at sites outside the mine. The sites selected represented a variety of geomorphic regions ranging from uranium-bearing rocks to ambient soils. Generally, wet season rains reduced 222Rn exhalation but at a few sites the onset of rains caused a step rise in exhalation flux densities. The results show that parameters such as 226Ra activity concentration, soil grain size and soil porosity have a marked effect on 222Rn flux densities. For similar geomorphic sites, 226Ra activity concentration is a dominant factor, but soil grain size and porosity also influence 222Rn exhalation. Surfaces with vegetation showed higher exhalation flux densities than their barren counterparts, perhaps because the associated root structure increases soil porosity and moisture retention. Repeated measurements over one year at eight sites enabled an analysis of precipitation and soil moisture effects on 222Rn exhalation. Soil moisture depth profiles varied both between seasons and at different times during the wet season, indicating that factors such as duration, intensity and time between precipitation events can influence 222Rn flux densities considerably.

  18. Removal of the long-lived 222Rn daughters from copper and stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zuzel, G.; Wójcik, M.

    2012-06-01

    Removal of the long-lived 222Rn daughters from copper and stainless steel surfaces was investigated. Etching and electropolishing were applied to discs exposed earlier to a strong radon source for 210Pb, 210Bi and 210Po deposition. Cleaning efficiency for 210Pb was tested with a n-type high purity germanium spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer was used. According to the performed measurements electropolishing removes very effectively all the isotopes from copper and stainless steel. Copper etching reduces efficiently lead and bismuth however for polonium the effect is negligible because of its fast re-deposition. For stainless steel, etching is much more effective compared to copper and it also works for 210Po.

  19. Partitioning of 222Rn entry into a structure surrounded by soil.

    PubMed

    Gadd, M S; Borak, T B

    1994-07-01

    This paper describes the entry rate of 222Rn into a basement structure surrounded by a sandy clay loam soil. The highest indoor radon concentrations occurred when the rate of entry was lowest. Data from in-situ measurements were used to identify the entry pathways and also the origins of the radon during periods when the entry rate was low. Results indicated that 25% of the radon entered through the floor-wall joint and 75% through the floor and walls. About 30% of the radon originated in the concrete. Diffusion was the primary transport mechanism. However, radon entry through the floor-wall joint was a combination of diffusion and a convective flow between the subslab region and the interior of the structure.

  20. Doses from 222Rn, 226Ra, and 228Ra in groundwater from Guarani aquifer, South America.

    PubMed

    Bonotto, D M

    2004-01-01

    Groundwater samples were analysed for 222Rn, 226Ra, and 228Ra in Guarani aquifer spreading around 1 million km2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay.

  1. Radon ((222)Rn) in underground drinking water supplies of the Southern Greater Poland Region.

    PubMed

    Bem, Henryk; Plota, Urszula; Staniszewska, Marta; Bem, Ewa Maria; Mazurek, Daria

    Activity concentration of the (222)Rn radionuclide was determined in drinking water samples from the Sothern Greater Poland region by liquid scintillation technique. The measured values ranged from 0.42 to 10.52 Bq/dm(3) with the geometric mean value of 1.92 Bq/dm(3). The calculated average annual effective doses from ingestion with water and inhalation of this radionuclide escaping from water were 1.15 and 11.8 μSv, respectively. Therefore, it should be underlined that, generally, it's not the ingestion of natural radionuclides with water but inhalation of the radon escaping from water which is a substantial part of the radiological hazard due to the presence of the natural radionuclides from the uranium and thorium series in the drinking water.

  2. Removal of long-lived 222Rn daughters by electropolishing thin layers of stainless steel

    NASA Astrophysics Data System (ADS)

    Schnee, R. W.; Bowles, M. A.; Bunker, R.; McCabe, K.; White, J.; Cushman, P.; Pepin, M.; Guiseppe, V. E.

    2013-08-01

    Long-lived alpha and beta emitters in the 222Rn decay chain on detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay. Removal of tens of microns of material via electropolishing has been shown to be effective at removing radon daughters implanted into material surfaces. Some applications, however, require the removal of uniform and significantly smaller thicknesses. Here, we demonstrate that electropolishing < 1 μm from stainless-steel plates reduces the contamination efficiently, by a factor > 100. Examination of electropolished wires with a scanning electron microscope confirms that the thickness removed is reproducible and reasonably uniform. Together, these tests demonstrate the effectiveness of removal of radon daughters for a proposed low-radiation, multi-wire proportional chamber (the BetaCage), without compromising the screener's energy resolution. More generally, electropolishing thin layers of stainless steel may effectively remove radon daughters without compromising precision-machined parts.

  3. High-resolution ion pulse ionization chamber with air filling for the 222Rn decays detection

    NASA Astrophysics Data System (ADS)

    Gavrilyuk, Yu. M.; Gangapshev, A. M.; Gezhaev, A. M.; Etezov, R. A.; Kazalov, V. V.; Kuzminov, V. V.; Panasenko, S. I.; Ratkevich, S. S.; Tekueva, D. A.; Yakimenko, S. P.

    2015-11-01

    The construction and characteristics of the cylindrical ion pulse ionization chamber (CIPIC) with a working volume of 3.2 L are described. The chamber is intended to register α-particles from the 222Rn and its daughter's decays in the filled air sample. The detector is less sensitive to electromagnetic pick-ups and mechanical noises. The digital pulse processing method is proposed to improve the energy resolution of the ion pulse ionization chamber. An energy resolution of 1.6% has been achieved for the 5.49 MeV α-line. The dependence of the energy resolution on high voltage and working media pressure has been investigated and the results are presented.

  4. Assessment of (222)Rn emanation from ore body and backfill tailings in low-grade underground uranium mine.

    PubMed

    Mishra, Devi Prasad; Sahu, Patitapaban; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2014-02-01

    This paper presents a comparative study of (222)Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, (226)Ra and moisture contents on (222)Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01 × 10(-3) and 1.03 Bq m(-2) s(-1), respectively. Significant positive linear correlations between (222)Rn emanation rate and the (226)Ra content of ore and tailings were observed. For normalised (226)Ra content, the (222)Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the (226)Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere.

  5. Effects of vegetation, a clay cap and environmental variables on 222Rn fluence rate from reclaimed U mill tailings.

    PubMed

    Morris, R C; Fraley, L

    1989-04-01

    We measured 222Rn fluence rate and several environmental variables on two plots with U mill tailings buried beneath 30 cm of overburden and 20 cm of topsoil. An additional 30 cm of clay covered the tailings on one plot and each plot was subdivided into bare soil and vegetated subplots. We used linear correlation, two-way ANOVA and stepwise multiple regression to analyze the effects of the plot characteristics and the environmental variables on 222Rn fluence rate. The most important effect on 222Rn fluence rates from these plots was the combination of a clay cap and a vegetated surface. The mean annual fluence rate from the plot having both of these characteristics (520 +/- 370 mBq m-2 s-1) was over three times that of the vegetated plot without a clay cap (170 +/- 130 mBq m-2 s-1) and 18 times that of the bare plot with a clay cap (29 +/- 13 mBq m-2 s-1). The interaction effect may have been due to the growth of roots in the moist clay and active transport of dissolved 222Rn to the surface in water. This speculation is supported by the observation that on vegetated plots with a clay cap, moisture in the clay enhanced the fluence rate.

  6. Estimation of submarine groundwater discharge and associated nutrient fluxes in eastern Laizhou Bay, China using 222Rn

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Li, Hailong; Wang, Xuejing; Zheng, Chunmiao; Wang, Chaoyue; Xiao, Kai; Wan, Li; Wang, Xusheng; Jiang, Xiaowei; Guo, Huaming

    2016-02-01

    There is increasing evidence that the inputs of nutrients to the Bohai Sea are closely related to submarine groundwater discharge (SGD). In this study, the naturally occurring isotope of radon (222Rn) was used as a tracer to assess SGD in eastern Laizhou Bay. The 222Rn concentration during a tidal period was measured continuously and a mass balance model that included atmospheric loss, tidal effects, mixing loss, diffusion from sediments, and SGD was established. The model budget indicated that 222Rn flux attributed to SGD accounted for 58.3% of the total tracer input to the study area. The time-series of 222Rn revealed that the SGD flux ranged from 6.64 to 7.21 cm d-1, with an average of 6.93 cm d-1, in September 2014. The estimated SGD flux is reasonable compared with those previously estimated in other studies by direct measurement methods, hydrogeological simulation and geochemical tracers. This result, as well as the current understanding of nutrients dissolved in groundwater, confirms the importance of SGD in delivering nutrients to Laizhou Bay and possible impact on marine ecological environment.

  7. What we can learn from measurements of air electric conductivity in 222Rn-rich atmosphere

    NASA Astrophysics Data System (ADS)

    Seran, E.; Godefroy, M.; Pili, E.; Michielsen, N.; Bondiguel, S.

    2017-02-01

    Electric conductivity of air is an important characteristic of the electric properties of an atmosphere. Testing instruments to measure electric conductivity ranging from 10-13 to 10-9 S m-1 in natural conditions found in the Earth atmosphere is not an easy task. One possibility is to use stratospheric balloon flights; another (and a simpler one) is to look for terrestrial environments with significant radioactive decay. In this paper we present measurements carried out with different types of conductivity sensors in two 222Rn-rich environments, i.e., in the Roselend underground tunnel (French Alps) and in the Institute of Radioprotection and Nuclear Safety BACCARA (BAnC de CAllibrage du RAdon) chamber. The concept of the conductivity sensor is based on the classical time relaxation method. New elements in our design include isolation of the sensor sensitive part (electrode) from the external electric field and sensor miniaturization. This greatly extends the application domain of the sensor and permits to measure air electric conductivity when the external electric field is high and varies from few tens of V m-1 to up to few tens of kV m-1. This is suitable to propose the instrument for a planetary mission. Two-fold objectives were attained as the outcome of these tests and their analysis. First was directly related to the performances of the conductivity sensors and the efficiency of the conductivity sensor design to shield the external electric field. Second objective aimed at understanding the decay mechanisms of 222Rn and its progeny in atmosphere and the impact of the enclosed space on the efficiency of gas ionization.

  8. Measurement of (222)Rn by absorption in plastic scintillators and alpha/beta pulse shape discrimination.

    PubMed

    Mitev, Krasimir K

    2016-04-01

    This work demonstrates that common plastic scintillators like BC-400, EJ-200 and SCSF-81 absorb radon and their scintillation pulse decay times are different for alpha- and beta-particles. This allows the application of pulse shape analysis for separation of the pulses of alpha- and beta-particles emitted by the absorbed radon and its progeny. It is shown that after pulse shape discrimination of beta-particles' pulses, the energy resolution of BC-400 and EJ-200 alpha spectra is sufficient to separate the peaks of (222)Rn, (218)Po and (214)Po and allows (222)Rn measurements that are unaffected by the presence of thoron ((220)Rn) in the environment. The alpha energy resolution of SCSF-81 in the experiments degrades due to imperfect collection of the light emitted inside the scintillating fibers. The experiments with plastic scintillation microspheres (PSM) confirm previous findings of other researchers that PSM have alpha-/beta-discrimination properties and show suitability for radon measurements. The diffusion length of radon in BC-400 and EJ-200 is determined. The pilot experiments show that the plastic scintillators are suitable for radon-in-soil-gas measurements. Overall, the results of this work suggest that it is possible to develop a new type of radon measurement instruments which employ absorption in plastic scintillators, pulse-shape discrimination and analysis of the alpha spectra. Such instruments can be very compact and can perform continuous, real-time radon measurements and thoron detection. They can find applications in various fields from radiation protection to earth sciences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Quantification of Submarine Groundwater Discharge Using a Radon (222-Rn) Mass Balance and Hydrogeological Modelling

    NASA Astrophysics Data System (ADS)

    Petermann, Eric; Stollberg, Reiner; Scholten, Jan; Knöller, Kay; Schubert, Michael

    2016-04-01

    Apart from river and surface water runoff subsurface discharge of groundwater plays a key role in coastal water and matter budgets. Two major forms of submarine groundwater discharge (SGD) can be distinguished: (i) pure freshwater discharge from continental aquifers that are connected to the coastal sea driven by a positive hydraulic gradient (fresh SGD) and (ii) re-circulation of seawater that has penetrated permeable coastal sediments (re-circulated SGD), e.g. driven by tidal pumping. The localization of SGD zones and the quantification of SGD fluxes is of high interest for coastal water management due to potential threats related to SGD, namely (i) the detrimental impact of discharging nutrient- or contaminant-laden groundwater on coastal seawater quality, an aspect that is of relevance along coastlines which are impacted by agriculture, industry or intense urbanization, and (ii) the loss of freshwater to the ocean, an issue that is of major relevance in all coastal areas with (seasonally) limited freshwater availability. In this work, we discuss estimates for the total (fresh + re-circulated) SGD fluxes derived from a mass balance of the radioactive noble gas radon (222-Rn) with estimates of fresh SGD fluxes derived by hydrogeological modelling. The precision of the mass balance results depends on the adequate determination of the mass balance source and sink terms. These terms are calculated based on field observations of environmental tracers (salinity, δ18O, 222-Rn, 223-Ra, 224-Ra, 226-Ra) in seawater and porewater, as well as on meteorological data. The numerical hydrogeological model estimates groundwater flow based on groundwater monitoring data, river flow data, groundwater recharge estimates, tidal dynamics, and density effects along the freshwater/seawater interface. We compare these two independent methodological approaches of SGD flux estimation, discuss results regarding their relevance for the regional water balance and reason the implications of

  10. Short-term 222Rn activity concentration changes in underground spaces with limited air exchange with the atmosphere

    NASA Astrophysics Data System (ADS)

    Fijałkowska-Lichwa, L.; Przylibski, T. A.

    2011-04-01

    The authors investigated short-time changes in 222Rn activity concentration occurring yearly in two underground tourist facilities with limited air exchange with the atmosphere. One of them is Niedźwiedzia (Bear) Cave in Kletno, Poland - a natural space equipped with locks ensuring isolation from the atmosphere. The other site is Fluorite Adit in Kletno, a section of a disused uranium mine. This adit is equipped with a mechanical ventilation system, operated periodically outside the opening times (at night). Both sites are situated within the same metamorphic rock complex, at similar altitudes, about 2 km apart. The measurements conducted revealed spring and autumn occurrence of convective air movements. In Bear Cave, this process causes a reduction in 222Rn activity concentration in the daytime, i.e. when tourists, guides and other staff are present in the cave. From the point of view of radiation protection, this is the best situation. For the rest of the year, daily concentrations of 222Rn activity in the cave are very stable. In Fluorite Adit, on the other hand, significant variations in daily 222Rn activity concentrations are recorded almost all year round. These changes are determined by the periods of activity and inactivity of mechanical ventilation. Unfortunately this is inactive in the daytime, which results in the highest values of 222Rn activity concentration at the times when tourists and staff are present in the adit. Slightly lower concentrations of radon in Fluorite Adit are recorded in the winter season, when convective air movements carry a substantial amount of radon out into the atmosphere. The incorrect usage of mechanical ventilation in Fluorite Adit results in the most unfavourable conditions in terms of radiation protection. The staff working in that facility are exposed practically throughout the year to the highest 222Rn activity concentrations, both at work (in the adit) and at home (outside their working hours). Therefore, not very well

  11. Contribution of (222)Rn-bearing water to indoor radon and indoor air quality assessment in hot spring hotels of Guangdong, China.

    PubMed

    Song, Gang; Wang, Xinming; Chen, Diyun; Chen, Yongheng

    2011-04-01

    This study investigates the contribution of radon ((222)Rn)-bearing water to indoor (222)Rn in thermal baths. The (222)Rn concentrations in air were monitored in the bathroom and the bedroom. Particulate matter (PM, both PM(10) and PM(2.5)) and carbon dioxide (CO(2)) were also monitored with portable analyzers. The bathrooms were supplied with hot spring water containing 66-260 kBq m(-3) of (222)Rn. The results show that the spray of hot spring water from the bath spouts is the dominant mechanism by which (222)Rn is released into the air of the bathroom, and then it diffuses into the bedroom. Average (222)Rn level was 110-410% higher in the bedrooms and 510-1200% higher in the bathrooms compared to the corresponding average levels when there was no use of hot spring water. The indoor (222)Rn levels were influenced by the (222)Rn concentrations in the hot spring water and the bathing times. The average (222)Rn transfer coefficients from water to air were 6.2 × 10(-4)-4.1 × 10(-3). The 24-h average levels of CO(2) and PM(10) in the hotel rooms were 89% and 22% higher than the present Indoor Air Quality (IAQ) standard of China. The main particle pollutant in the hotel rooms was PM(2.5). Radon and PM(10) levels in some hotel rooms were at much higher concentrations than guideline levels, and thus the potential health risks to tourists and especially to the hotel workers should be of great concern, and measures should be taken to lower inhalation exposure to these air pollutants.

  12. Continuous atmospheric 222Rn concentration measurements to study surface-air exchange at the station of Gredos and Iruelas, in Central Spain

    NASA Astrophysics Data System (ADS)

    Grossi, Claudia; Morgui, Josep Anton; Àgueda, Alba; Batet, Oscar; Curcoll, Roger; Arias, Rosa; Arnold, Delia; Ealo, Marina; Nofuentes, Manel; Occhipinti, Paola; Sánchez-Garcíaa, Laura; Vargas, Arturo; Rodó, Xavier

    2013-04-01

    The Gredos and Iruelas station (GIC3) is part of the ClimaDat IC3 network (http://climadat.es/). This station is located in the Gredos Natural Park at a latitude of 40.22° N and a longitude of -5.14° E in the Spanish central plateau. The ClimaDat network is made by 8 stations distributed around Spain and it has been developed with the aim of studying climatic processes and the responses of impacted systems, at different time and space scales. Since November 2012, measurements of CO2, CH4, and of the natural radioactive gas 222Rn are continuously performed at GIC3 station at 20 m agl and at 1100 m asl . Maximum,minimum and average values of meteorological parameters, such as ambient air humidity and temperature, wind speed and direction are also measured at GIC3 station. Particularly, the concentration series of 222Rn measured at GIC3 station are extremely useful to evaluate the exchange of this noble radioactive gas between the soil surface and the lower troposphere in this area, under different weather situations and environmental conditions. The Gredos Natural Park is located in a granitic basement and this type of soil presents a high porosity and permeability. Furthermore, granitic materials have high activity levels of 228U. These factors enable large amount of radon to escape from the deeper soil, giving radon flux values of 90-100 Bq m-2 h-1 . These radon flux values are much higher than the average radon flux over the Earth, which is about 50 Bq m-2 h-1 (Szegvary et al, 2009). On the other hand, this geographical area is frequently affected by snow and rain events which drastically reduce the local radon exhalation. It is also influenced by winds coming from the Atlantic Ocean, which are poor in radon and strong, causing an important mixing. In addition, the cold nights' stability leads to an observed nocturnal radon accumulation. All the aforementioned conditions influence atmospheric radon concentrations measured at the GIC3 station, enlarging the range

  13. Removal of long-lived {sup 222}Rn daughters by electropolishing thin layers of stainless steel

    SciTech Connect

    Schnee, R. W.; Bowles, M. A.; Bunker, R.; McCabe, K.; White, J.; Cushman, P.; Pepin, M.; Guiseppe, V. E.

    2013-08-08

    Long-lived alpha and beta emitters in the {sup 222}Rn decay chain on detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay. Removal of tens of microns of material via electropolishing has been shown to be effective at removing radon daughters implanted into material surfaces. Some applications, however, require the removal of uniform and significantly smaller thicknesses. Here, we demonstrate that electropolishing < 1 μm from stainless-steel plates reduces the contamination efficiently, by a factor > 100. Examination of electropolished wires with a scanning electron microscope confirms that the thickness removed is reproducible and reasonably uniform. Together, these tests demonstrate the effectiveness of removal of radon daughters for a proposed low-radiation, multi-wire proportional chamber (the BetaCage), without compromising the screener’s energy resolution. More generally, electropolishing thin layers of stainless steel may effectively remove radon daughters without compromising precision-machined parts.

  14. Prediction of 222Rn in Danish dwellings using geology and house construction information from central databases.

    PubMed

    Andersen, Claus E; Raaschou-Nielsen, Ole; Andersen, Helle Primdal; Lind, Morten; Gravesen, Peter; Thomsen, Birthe L; Ulbak, Kaare

    2007-01-01

    A linear regression model has been developed for the prediction of indoor (222)Rn in Danish houses. The model provides proxy radon concentrations for about 21,000 houses in a Danish case-control study on the possible association between residential radon and childhood cancer (primarily leukaemia). The model was calibrated against radon measurements in 3116 houses. An independent dataset with 788 house measurements was used for model performance assessment. The model includes nine explanatory variables, of which the most important ones are house type and geology. All explanatory variables are available from central databases. The model was fitted to log-transformed radon concentrations and it has an R(2) of 40%. The uncertainty associated with individual predictions of (untransformed) radon concentrations is about a factor of 2.0 (one standard deviation). The comparison with the independent test data shows that the model makes sound predictions and that errors of radon predictions are only weakly correlated with the estimates themselves (R(2) = 10%).

  15. In-situ determination of the diffusion coefficient of 222Rn in concrete.

    PubMed

    Gadd, M S; Borak, T B

    1995-06-01

    Measurements of the effective diffusion coefficient, De, of 222Rn in concrete are important for accurate determination of transport mechanisms and computer modeling of radon entry into structures. A method for in-situ determination of De as well as the emanation fraction, F, is described. It is based on continuous measurement of the radon flux from an intact slab and the concentrations on both sides. A non-linear regression algorithm was used to fit these data to the steady state solution to Fick's law. The regression output includes estimates of both De and F. The method has the advantage over typical laboratory procedures since it measures an undisturbed surface area of concrete where the samples exhibit moisture, temperature, and loading conditions that are experienced in a real structure. Effective diffusion coefficients ranged from 1.1 x 10(-8) to 4.4 x 10(-8) m2 s-1 for measurements of concrete floor slabs in two structures. The measured emanation fraction of radon in concrete in one structure was 0.2 +/- 0.02. A sensitivity analysis indicated that the values of De and F estimated by the regression procedure are strongly dependent on the thickness of the slab. The porosity of the concrete had little affect on the regression results.

  16. Real-time radon monitoring at Stromboli volcano: influence of environmental parameters on 222Rn degassing

    NASA Astrophysics Data System (ADS)

    Cigolini, C.; Ripepe, M.; Poggi, P.; Laiolo, M.

    2008-12-01

    Two real-time stations for radon monitoring are currently operative at Stromboli volcano. The 222Rn electronic dosimeters are interfaced with an electronic board connected to a radiomodem for wireless data transfer (through a directional antenna) to a receiving station at the volcano observatory (COA). Radon activity data and enviromental parameters (soil temperature and atmospheric pressure) are sampled every 15 minutes and are instantaneously elaborated and transferred via web so that they can be checked in remote. Collected time series show that there is an overall inverse correlation between radon emissions and seasonal temperature variations. Signal processing analysis show that radon emissions in sectors of diffuse degassing are modulated by tidal forces as well. In addition, radon activities recorded at the summit station, located along the summit fracture zone where the gas flux is concentrated, are positively correlated with changes in atmospheric pressure and confirm the occurrence of the 'atmospheric stack effect'. It is not excluded that this process may play an active role in modulating Stromboli explosivity.

  17. /sup 222/Rn and atmospheric electrical parameters in the Carlsbad Caverns

    SciTech Connect

    Wilkening, M.; Romero, V.

    1981-10-20

    Atmospheric electrical parameters have been investigated in the Carlsbad Caverns. /sup 222/Rn concentrations of the order of 65 pCi/l in the Caverns during the summer maximum results in a high rate of ion-pair production estimated to be about 2300 x 10/sup 6/ ion pairs m/sup -3/ s/sup -1/. This leads to ion densities of about a thousand times that of the free atmosphere. Electrical conductivity values of approximately 150 x 10/sup -14/ (..cap omega.. m)/sup -1/ were measured which exceed those of outdoor air by a factor of the order of 100. Mobilities for positive and negative small-ion populations in the Caverns during the summer, appear to be less than mobilities reported for small ions in the free atmosphere. The lower mobility of the cave ions relative to outdoor fair-weather conditions is attributed to a combination of high humidity and low condensation nuclei concentration in the cave enviroment. An electric field of approximately 1 V m/sup -1/ was measured near the floor of a tunnel in the Caverns. This suggests the presence of net negative space charge equivalent to about 0.4 x 10/sup 8/ ion m/sup -3/.

  18. Outdoor (222)Rn-concentrations in Germany - part 1 - natural background.

    PubMed

    Kümmel, M; Dushe, C; Müller, S; Gehrcke, K

    2014-06-01

    To determine the natural radiation exposure due to outdoor radon ((222)Rn) and its short-lived decay products in Germany, the Federal Office for Radiation Protection (BfS) conducted a measuring programme over three years. The annual mean radon concentration at 1.5 m above ground level was measured with solid-state track etch detectors at 173 measuring points in an even grid with a grid length of approx. 50 km. Furthermore, annual mean values of the equilibrium-equivalent radon concentration (EEC) and the equilibrium factor were estimated on the basis of the activity concentrations of (214)Pb and (214)Bi measured at 27 stations of the German Meteorological Service (DWD). Our study yielded a spatial mean outdoor radon concentration for Germany of 9 ± 1 Bq m(-3) (median: 8 (-0.5/+1.0) Bq m(-3)), with regional means varying from 4.5 Bq m(-3) in Hamburg to 14 Bq m(-3) in Bavaria. The determined EEC are in a range from 1.4 to 11 Bq m(-3).

  19. Monte Carlo simulation of semiconductor detector response to (222)Rn and (220)Rn environments.

    PubMed

    Irlinger, J; Trinkl, S; Wielunksi, M; Tschiersch, J; Rühm, W

    2016-07-01

    A new electronic radon/thoron monitor employing semiconductor detectors based on a passive diffusion chamber design has been recently developed at the Helmholtz Zentrum München (HMGU). This device allows for acquisition of alpha particle energy spectra, in order to distinguish alpha particles originating from radon and radon progeny decays, as well as those originating from thoron and its progeny decays. A Monte-Carlo application is described which uses the Geant4 toolkit to simulate these alpha particle spectra. Reasonable agreement between measured and simulated spectra were obtained for both (220)Rn and (222)Rn, in the energy range between 1 and 10 MeV. Measured calibration factors could be reproduced by the simulation, given the uncertainties involved in the measurement and simulation. The simulated alpha particle spectra can now be used to interpret spectra measured in mixed radon/thoron atmospheres. The results agreed well with measurements performed in both radon and thoron gas environments. It is concluded that the developed simulation allows for an accurate prediction of calibration factors and alpha particle energy spectra.

  20. Role of gas exchange in the inorganic carbon, oxygen, and /sup 222/Rn budgets of the Amazon River

    SciTech Connect

    Devol, A.H.; Quay, P.D.; Richey, J.E.; Martinelli, L.A.

    1987-01-01

    Dissolved oxygen, /sup 222/Rn, pCO/sub 2/, alkalinity, respiration rate, and discharge have been measured at eight mainstem and seven tributary stations during February-March 1984 in a 1700-km stretch of the Amazon River between Vargem Grande and Obidos in Brazil. Air-water gas exchange rates were estimated two ways: measurements of the flux of /sup 222/Rn int floating domes yielded an average boundary layer thickness of 78..mu..m, and oxygen mass balance calculations resulted in an average of 38..mu..m. Given a boundary layer thickness on the order of 50..mu..m, CO/sub 2/ loss to the atmosphere in the entire reach would have been 37.4 kmol s/sup -1/, which is about equal to the total tributary dissolved inorganic carbon (DIC) input and is about half of the total fluvial DIC input to the section. Thus, CO/sub 2/ evasion is a major component of Amazon River DIC balance. Because gas exchange within the section was rapid relative to water travel time through the section, a quasi-steady state was maintained between respiratory input and evasion of CO/sub 2/. Dissolved /sup 222/Rn activities in the mainstem varied from 3.5 to 8.3 dpm liter/sup -1/ and were always highly supersaturated with respect to the atmosphere. Dissolved radon was also not supported by decay of /sup 222/Ra in the mainstem. A /sup 222/Rn mass balance indicated that direct groundwater input into this stretch of the Amazon mainstem probably accounted for no more than 1% of water discharge.

  1. An International Marine-Atmospheric (222)Rn Measurement Intercomparison in Bermuda Part II: Results for the Participating Laboratories.

    PubMed

    Collé, R; Unterweger, M P; Hutchinson, J M R; Whittlestone, S; Polian, Georges; Ardouin, Bénédicte; Kay, Jack G; Friend, James P; Blomquist, Byron W; Nadler, Wolfgang; Dang, Thomas T; Larsen, R J; Hutter, A R

    1996-01-01

    As part of an international measurement intercomparison of instruments used to measure atmospheric (222)Rn, four participating laboratories made nearly simultaneous measurements of (222)Rn activity concentration in commonly sampled, ambient air over approximately a 2 week period, and three of these four laboratories participated in the measurement comparison of 14 introduced samples with known, but undisclosed ("blind") (222)Rn activity concentration. The exercise was conducted in Bermuda in October 1991. The (222)Rn activity concentrations in ambient Bermudian air over the course of the intercomparison ranged from a few hundredths of a Bq · m(-3) to about 2 Bq · m(-3), while the standardized sample additions covered a range from approximately 2.5 Bq · m(-3) to 35 Bq · m(-3). The overall uncertainty in the latter concentrations was in the general range of 10 %, approximating a 3 standard deviation uncertainty interval. The results of the intercomparison indicated that two of the laboratories were within very good agreement with the standard additions, and almost within expected statistical variations. These same two laboratories, however, at lower ambient concentrations, exhibited a systematic difference with an averaged offset of roughly 0.3 Bq · m(-3). The third laboratory participating in the measurement of standardized sample additions was systematically low by about 65 % to 70 %, with respect to the standard addition which was also confirmed in their ambient air concentration measurements. The fourth laboratory, participating in only the ambient measurement part of the intercomparison, was also systematically low by at least 40 % with respect to the first two laboratories.

  2. Distribution of 222Rn concentration in an inhabited area adjacent to the Aja granitic heights of Hail Province, Saudi Arabia.

    PubMed

    Kinsara, Abdulraheem Abdulrahman; Shabana, El-Said Ibrahim; Abulfaraj, Waleed Hussain; Qutub, Maher Mohammad Taher

    2015-01-01

    Radon-222 has been measured in groundwater, dwellings, and atmosphere of an inhabited area adjacent to the granitic Aja heights of Hail province, Saudi Arabia. The measurements were carried out in the field using a RAD7 instrument. Twenty-eight water samples, collected from drilled wells scattered in the region, were analyzed. Radon-222 concentration ranged from 2.5-95 kBq m(-3) with an average value of about 30.3 kBq m(-3). The higher values were found in wells drawing water from granitic aquifers. Indoor 222Rn was measured in 20 dwellings of rural areas in Hail city and other towns. Concentrations ranged from 12-125.6 Bq m(-3), with an average value of 54.6 Bq m(-3). Outdoor air 222Rn was measured at 16 sites, with values ranging from 6.2-13.3 Bq m(-3), with an average value of 10.5 Bq m(-3). The estimated average effective dose due to inhalation of 222Rn released from water was 0.08 mSv y(-1). The estimated average annual effective dose due to indoor 222Rn was 1.35 mSv, which lies below the effective dose range (3-10 mSv) given as the recommended action level. Based on the average dose rate values, the excess lifetime cancer risk values were estimated as 69.8 × 10(-4) due to indoor radon and 13.4 × 10(-4) due to outdoor radon.

  3. Precise measurement of the 222Rn half-life: A probe to monitor the stability of radioactivity

    NASA Astrophysics Data System (ADS)

    Bellotti, E.; Broggini, C.; Di Carlo, G.; Laubenstein, M.; Menegazzo, R.

    2015-04-01

    We give the results of a study on the 222Rn decay we performed in the Gran Sasso Laboratory (LNGS) by detecting the gamma rays from the radon progeny. The motivation was to monitor the stability of radioactivity measuring several times per year the half-life of a short lifetime (days) source instead of measuring over a long period the activity of a long lifetime (tens or hundreds of years) source. In particular, we give a possible reason of the large periodical fluctuations in the count rate of the gamma rays due to radon inside a closed canister which has been described in literature and which has been attributed to a possible influence of a component in the solar irradiation affecting the nuclear decay rates. We then provide the result of four half-life measurements we performed underground at LNGS in the period from May 2014 to January 2015 with radon diffused into olive oil. Briefly, we did not measure any change of the 222Rn half-life with a 8 ṡ10-5 precision. Finally, we provide the most precise value for the 222Rn half-life: 3.82146(16)stat(4)syst days.

  4. Occurrence of {sup 222}Rn in irrigation water from Wadi Al-Rummah Qassim province, Saudi Arabia

    SciTech Connect

    El-Taher, Atef; Alashrah, Saleh

    2015-08-28

    Naturally accruing radioactive materials in the environment have received attention since they may be present in high level and pose risk to human health. The present work deals with measuring of {sup 222}Rn in irrigation water samples from Wadi Al-Rummah, Qassim province, in central of Saudi Arabia. {sup 222}Rn concentrations were measured by RAD7. It was found that the concentration of {sup 222}Rn ranged from 2.1 ± 1.2 to 7.2 ± 1.5 BqL{sup −1}. These values are below 11.1 BqL{sup −1} the maximum contamination level recommended from the U.S. Environmental Protection Agency. The calculated annual effective dose (AED) ranging from 7.5 to 26.1 µSv/y. It was evident that the total annual effective dose resulting from radon in irrigation groundwater in Wadi Al-Rummah in Qassim area were significantly lower than the recommended limit 1 mSv/y for the public.

  5. Using 222Rn to examine groundwater/surface discharge interaction in the Rio Grande de Manati, Puerto Rico

    USGS Publications Warehouse

    Ellins, K.K.; Roman-Mas, A.; Lee, R.

    1990-01-01

    222Rn was used in the karst drainage basin of the Rio Grande de Manati in Puerto Rico to study groundwater/surface flow relationships. Locations of groundwater influx along two sections of the Rio Grande de Manati were identified. The 222Rn measurements were used together with stream discharge data in a mass balance equation to quantify the groundwater inputs. The investigation established that both of the sections of the Rio Manati surveyed not only gained groundwater, but lost surface flow. It was calculated that the river gained about 1.2m3s-1 and lost 0.5m3s-1 to the aquifer between Ciales and United States Geological Survey gauging station 5. Between United States Geological Survey gauging stations 6 and 7, groundwater influx and stream flow loss occurred simultaneously with groundwater inputs equalling surface discharge losses of 4m3s-1. The study successfully demonstrated the innovative application of 222Rn as a geochemical tracer in examining groundwater/surface flow relationships in a karst system. ?? 1990.

  6. 222Rn behavior in waters from peatlands and eskers of the Amos region, Abitibi-Temiscamingue, Québec, Canada

    NASA Astrophysics Data System (ADS)

    Berthot, Laureline; Boucher, Christine; Pinti, Daniele Luigi; Larocque, Marie; Ferlatte, Miryane; Gagné, Sylvain

    2013-04-01

    222Rn is a short decay product of U. Being a noble gas not affected by chemical reactions 222Rn can be a suitable tracer in subsurface hydrology, particularly for stream-groundwater interactions. We recently carried out a Quebec government-funded project for characterizing the hydrological cycle in peatlands located around fluvioglacial moraines and eskers in the Abitibi-Temiscamingue region of Québec, eastern Canada. The goal of this project was to trace water exchanges between the eskers and the surrounding peatlands using stable isotopes, major chemistry and noble gases (including 222Rn). Samples were taken in summer 2012 from 46 wells tapping the Saint-Mathieu-de-Berry and Barraute eskers and the Harricana moraine. Sixteen samples were taken from deeper wells tapping the Archean fractured bedrock in the clay plain separating these eskers. And 40 samples were collected from piezometers installed at different depths from 0.70m to 4.8 m in four peatlands located along the flanks of the Saint-Mathieu-de-Berry esker and the Harricana moraine. 222Rn activity was measured at UQAM using a liquid scintillation counter (SL-300 from HIDEX®). 222Rn activities in peatland water range from 0.02 to 16.6 Bq/L. 222Rn activities measured in groundwater flowing through the esker and moraine aquifers range from 2.8 to 34.9 Bq/L. These values are relatively low taking into account that the rock matrix derives from old Archean granitoids and volcanic rock likely rich in U and Th. However, 234U/238U analyses in the same waters showed that these hydrologic systems are extremely depleted in U-derived radionuclides. Interestingly, several peatlands show a good correlation between the Total Dissolved Salinity (TDS) and the 222Rn activity and with HCO3-, SO42-, Mg2+ and Ca2+. Salinity in the eskers derives from the deeper fractured basement aquifer as indicated by a clear correlation between helium isotopes, TDS and the well depths. A similar relation is observed for the 222Rn. This

  7. Seasonal Variation of Unattached fraction and Equilibrium factor of 222Rn and 220Rn using DRPS/DTPS and Pin -hole cup dosimeters.

    NASA Astrophysics Data System (ADS)

    Bangotra, P.; Mehra, R.; Jakhu, R.

    2015-12-01

    222Rn (Radon), 220Rn (Thoron) and their progenies are naturally occurring radionuclides in environment and responsible for the radiological dose to population. The 222Rn, 220Rn concentration and their separate attached and unattached progeny concentration (season-wise) in units of EEC have been measured in the dwellings of Muktsar and Mansa districts of Punjab (India), using Pin- hole cup dosimeters and deposition based progeny sensors (DTPS/DRPS). The indoor 222Rn concentration was maximum in the rainy season (60 Bqm-3) while 220Rn concentration was maximum in winter season (57 Bqm-3). However EEC of 222Rn and 220Rn has distinct seasonal demeanour than their parent nuclides. The unattached EEC for both 222Rn and 220Rn (EERCU and EETCU) were higher in summer and rainy season as compared to winter season. The equilibrium factor ( for 222Rn and for 220Rn) and unattached fraction ( for 222Rn and for 220Rn) has been calculated separately. The (0.44 ± 0.04) in the studied area was similar to 0.4 that proposed by UNSCEAR and for (0.05 ± 0.01) it was greater than specified value 0.02 by UNSCEAR. The was higher in summer season as compared to rainy and winter season. Due to very smaller value of , a proper relation has not been observed seasonally. The unattached fraction in environment may increase the risk of radiological exposure and absorbed at faster rate into blood then the attached 222Rn and 220Rn progeny. The overall arithmetic mean (rainy, winter and summer seasons) of and were 0.09 ± 0.02 and 0.10 ± 0.03 respectively. The and were lower in winter season as compared to rainy and summer seasons due to higher value of attached EEC present in winter season. A positive and significant correlation (0.56) has been observed between the and aerosol concentration (Z (cm-3)).

  8. Modelling the effect of air exchange on 222Rn and its progeny concentration in a tunnel atmosphere.

    PubMed

    Perrier, Frédéric; Richon, Patrick; Sabroux, Jean-Christophe

    2005-11-01

    The effect of air exchange on the concentration of 222Rn and its progeny in the atmosphere of the Roselend tunnel, in the French Alps, is estimated using a box modelling scheme. In this scheme, the atmosphere is divided into a small number of well mixed zones, separated by flow restricted interfaces, characterized by their exchange rate. A four-box model, representing the three sections of the tunnel present until 2001 and an adjacent inner room, accounts for the spatial variations of the background 222Rn concentration, and for the time structure of transient bursts observed regularly in this tunnel since 1995. A delay of the order of one day, observed during some transient bursts in the inner room with respect to the end of the tunnel, is accounted for if the bursts are assumed to be mainly generated in the end section of the tunnel, and stored temporarily in the inner room via air exchange. The measured radon concentration is reproduced by this model for an air exchange rate of 1.6x10(-6) s-1 between the room and the tunnel, in a context of a global ventilation rate of 10(-5) s-1 in the tunnel. Gradual onset and decay phases, varying from burst to burst, are also suggested. The equilibrium factor of 222Rn with its progeny, measured in 2002 with values varying from 0.60+/-0.05 to 0.78+/-0.06, is interpreted with a five-box model representing the five sections of the tunnel present after 2001. This model indicates that the equilibrium factor does not provide additional constraints on the air exchange rates, but the value of the deposition rate of the unattached short-lived radon progeny can be inferred, with results varying from 0.2 to 6 h-1 in the various sections. This study illustrates the benefits of a simple modelling tool to evaluate the effect of natural ventilation on 222Rn and its progeny concentration in underground cavities, which is important for radioprotection and for a reliable characterization of signatures of hydrogeological or geodynamical

  9. The role of mesoscale meteorology in modulating the (222)Rn concentrations in Huelva (Spain)--impact of phosphogypsum piles.

    PubMed

    Hernández-Ceballos, M A; Vargas, A; Arnold, D; Bolívar, J P

    2015-07-01

    The combined analysis of (222)Rn activity concentrations and mesoscale meteorological conditions at Huelva city (Spain) was addressed in this study to understand the potential impact of phosphogypsum piles on the (222)Rn activity concentrations registered at this area. Hourly mean data from April 2012 to February 2013 registered at two sampling sites (Huelva city and in the background station of El Arenosillo, located 27 km to the south-east) have been used in the study. The results of the present study showed a large difference in mean radon concentrations between the two stations during the sampling period, 6.3 ± 0.4 Bq m(-3) at Huelva and 3.0 ± 0.2 Bq m(-3) at El Arenosillo. The analysis has demonstrated that hourly (222)Rn concentrations at Huelva city above 22 Bq m(-3), with nocturnal peaks up to 50 Bq/m(3), mainly coincided with the occurrence of a pure sea-land breeze cycle. Mesoscale circulations in this region are mainly characterized by two patterns of sea-land breeze, pure and non-pure, with the phosphosypsum piles directly upstream (south) of the city during the afternoon on pure sea-breeze days. The difference between mean (222)Rn activity concentrations at Huelva city were 9.9 ± 1.5 Bq m(-3) for the pure pattern and 3.3 ± 0.5 Bq m(-3) for the non-pure pattern, while in the background station concentrations were 3.9 ± 0.4 Bq m(-3) and 2.8 ± 0.4 Bq m(-3) respectively. Considering these large differences, a detailed analysis of composites and case studies of representative sea-land breeze cycles of both types and their impact on (222)Rn activity concentration was performed. The results suggested that the presence of the phosphogypsum piles was necessary in order to justify the high (222)Rn activity concentrations observed at Huelva compared with the background station in the afternoons on pure sea breeze days (1.5-2.0 Bq m(-3)). On the other hand, large night time differences between the two sites on these days were

  10. Use of 222Rn as natural tracer for LNAPL quantification and recovery efficiency in a crude-oil contaminated aquifer

    NASA Astrophysics Data System (ADS)

    Ponsin, Violaine; Chablais, Amélie; Dumont, Julien; Cardetti, Marc; Radakovitch, Olivier; Höhener, Patrick

    2014-05-01

    In august 2009, five hectares of the pristine gravel aquifer of Crau in southern France were contaminated by 5,100 m3 of crude oil due to the sudden break of a pipeline. The remediation of this site is still ongoing and consists in replacement and off-site disposal of contaminated topsoils, plume management by hydraulic groundwater barriers with re-injection of activated charcoal-treated waters, and dual-phase LNAPL extraction in the source zone. It is anticipated to stop these remediation actions when the rate of hydrocarbon extraction becomes inefficient. The volume of LNAPL is estimated between 100 and 1000 m3. A more accurate estimation is needed for the implementation of natural attenuation once physical treatment is discontinued. 222Rn has been introduced as a natural tracer for the quantification of LNAPL saturation in porous media under natural gradient conditions (Hunkeler et al., 1997; Semprini et al., 2000; Schubert et al., 2007). The objective of this study was to investigate whether 222Rn in groundwater can be used as a tracer for LNAPL quantification at a field site treated by LNAPL removal. To this end, groundwater samples were obtained in pristine monitoring wells from upgradient the contamination using submersible electric pumps, and in LNAPL recovery wells. There, samples were obtained from the tap on the hard PVC tubing used for pumping groundwater to the treatment facility. For 222Rn analysis, flasks of 250 mL were gently filled and were capped thereafter without permitting air bubbles. The flasks were analysed within 6 to 24 hours. The 222Rn activity of groundwater was measured by a Rn detector (RAD7-Durridge, Co. Inc.). The measurements were spaced over more than 15 months in order to account for seasonal changes. Each well was sampled at least 3 times. In pristine groundwater, the radon activity was relatively constant and remained always > 14 Bq/L. The radon activities in the groundwater of source zone wells were also relatively constant and

  11. Comprehensive software for the assessment of 222Rn and 220Rn decay products based on air sampling measurements.

    PubMed

    Sima, Octavian

    2009-05-01

    A computational tool dedicated to the measurement of (222)Rn and (220)Rn decay products by air sampling is presented. alpha- or gamma-spectrometry measurements, gross alpha or beta counting, as well as a combination of them are considered. Special attention is given to the evaluation of the uncertainty budget of the results. Besides typical applications in the analysis of experimental data, the software can be used for assessing the expected quality of a measurement protocol and for optimizing it, by generating and analyzing sets of realistic synthetic data.

  12. Improvement of measuring methods and instrumentation concerning (222)Rn determination in drinking waters - RAD7 and LSC technique comparison.

    PubMed

    Stojković, Ivana; Tenjović, Branislava; Nikolov, Jovana; Vesković, Miroslav; Mrđa, Dušan; Todorović, Nataša

    2015-04-01

    A procedure for the determination of (222)Rn in environmental water samples using liquid scintillation counting (LSC) was applied and optimized. A minimum detectable activity of 0.029Bql(-1) in a 20ml glass vial (10ml water sample mixed with 10ml of liquid scintillation cocktail) has been achieved during 300min of measurement time. The procedure was compared with RAD7 radon detector measurements. (226)Ra content in the water was determined by gamma-ray spectroscopy. Applications to drinking waters collected from public drinking fountains in the Vojvodina (Serbia) are presented with annual effective dose for ingestion and inhalation for adults calculated.

  13. A theoretical model for {sup 222}Rn adsorption on activated charcoal canisters in humid air based on Polanyi`s potential theory

    SciTech Connect

    Scarpitta, S.C.

    1995-03-01

    Water vapor interferes with adsorption {sup 222}Rn gas by passive activated charcoal devices used to estimate indoor air concentrations. The {sup 222}Rn adsorption coefficient is the fundamental parameter characterizing charcoal`s ability to adsorb {sup 222}Rn. The Dubinin-Radushkevich equation, based on Polanyi`s potential theory, was modified to include two terms quantifying the effect of both water vapor and sampling time on the {sup 222}Rn adsorption coefficient of passive charcoal devices. A single equation was derived that quantities the {sup 222}Rn adsorption coefficients at any temperature, humidity and exposure time using six experimentally determined physical constants that are unique for a particular passive charcoal device. The theoretical model was verified with published experimental data, and it showed a good correlation between theory and experiment. The model proved to be consistent with experimental data, provided that the amount of water vapor adsorbed by the charcoal device during sampling remains below a critical level, termed the breakpoint. 44 refs., 5 figs., 2 tabs.

  14. The activity concentrations of 222Rn and corresponding health risk in groundwater samples from basement and sandstone aquifer; the correlation to physicochemical parameters

    NASA Astrophysics Data System (ADS)

    Abdurabu, Wedad Ali; Ramli, Ahmad Termizi; Saleh, Muneer Aziz; Heryansyah, Arien

    2016-10-01

    This study aims to evaluate the activity concentrations of 222Rn and to assess the corresponding health risk in groundwater samples obtained in Juban District, Ad Dali' Governorate, Yemen. The measurements were performed by RAD 7 radon detector manufactured by DURRIDGE COMPANY Inc. The activity concentrations of 222Rn ranged from 1.0±0.2 Bq l-1 to 896.0±0.8 Bq l-1. 57% of the groundwater samples were above the US Environmental Protection Agency (USEPA) recommended value for Rn in water. Induced coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of uranium in groundwater samples. The measured concentration of U ranged from 0.33±0.01 μg l-1 to 24.6±0.6 μg l-1. The results were comparable to internationally recommended values. The highest concentration of U and 222Rn were found to be in the basement aquifer, while the lowest concentrations of both radionuclides were in the sandstone aquifer. High concentrations of Rn are found along fault zones. The relationship between the activity concentration of 222Rn, concentration of U and physicochemical parameters were investigated. The results showed a very strong relationship between activity concentrations of 222Rn with concentrations of U and the salinity of water.

  15. [The determination of {sup 222}Rn flux from soils based on {sup 210}Pb and {sup 226}Ra disequilibrium]. Progress report

    SciTech Connect

    Turekian, K.K.

    1991-12-31

    The emanating fraction of radon in soils from the southern part of the United States is about 40% greater than in those from the northern part. The mean {sup 226}Ra activity in the southern soils is also slightly higher and as a consequence the {sup 222}Rn flux derived from the top 50 cm. is greater in the southern samples. We tentatively attribute these observations to the greater degree of weathering associated with the pre-glacial age of the parent material of many of the southern soils. The weathering has concentrated {sup 226}Ra near grain surfaces and results in an increased emanating power for {sup 222}Rn. The estimated correction in {sup 210}Pb analyses described above results in a small decrease in our estimate of the mean loss rate of {sup 222}Rn from the upper 50 cm of soils.

  16. Seismo-volcanic monitoring at Furnas Volcano (Azores): radon (222Rn) concentration in groundwater

    NASA Astrophysics Data System (ADS)

    Silva, Catarina; Virgílio Cruz, José; Ferreira, Teresa; Viveiros, Fátima; Freire, Pedro; Allard, Patrick

    2017-04-01

    The Azores archipelago, located in the middle of the North Atlantic Ocean, is composed of nine volcanic islands that formed at the triple junction of the North American, Eurasian and African (Nubian) tectonic plates. These volcanic islands were the sites of several eruptions and destructive earthquakes since human settlement in the 15th century. S. Miguel Island, the largest and most densely populated island of the Azores, hosts three active strato-volcanoes with calderas. Furnas Volcano is one of these. Its eruptive activity has been essentially explosive, involving magmas with trachytic (s.l.) composition. In the last 5000 years at least 10 explosive eruptions occurred inside the caldera of Furnas. The last one occurred in 1630 and was subplinian in character. Since then an intense hydrothermal activity has persisted, involving four main fumarolic fields, thermal springs, CO2-rich springs, several soil diffuse degassing areas (CO2 and 222Rn), as well as occasional hydrothermal explosions. In the past decade we have developed a radon survey of Furnas hydrothermal manifestations. Here we report on the radon survey of twelve water springs, located inside the caldera, and representative of the different water types encountered at the volcano (orthothermal, thermal and CO2-rich springs). Bimonthly sampling and determination of radon activity and water temperature was performed in the selected springs between years 2007 and 2011. At each sampling point two water samples were collected for radon dosing in laboratory with the RAD7 equipment. A decay correction was applied to each sample. The average radon activities were found to vary between 1.15 Bq/L and 29.77 Bq/L, while water temperatures ranged between 16.5 °C and 76.2 °C. As a whole radon activities inversely correlate with water temperature, with orthothermal springs showing higher radon activity than thermal springs. Temporal variations in both parameters appear to be mainly determined by seasonal variations of

  17. Diffuse CO_{2} and ^{222}Rn degassing monitoring of Ontake volcano, Japan

    NASA Astrophysics Data System (ADS)

    Alonso, Mar; Sagiya, Takeshi; Meneses-Gutiérrez, Ángela; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.; Melián, Gladys; Padilla, Germán D.

    2017-04-01

    Mt. Ontake (3067 m.a.s.l.) is a stratovolcano located in central Honsu and around 100 Km northeast of Nagoya, Japan, with the last eruption occurring on September 27, 2014, killing 57 people, and creating a 7-10 km high ash plume (Kagoshima et. al., 2016). There were no significant earthquakes that might have warned authorities in the lead up to the phreatic eruption, caused by ground water flashing to steam in a hydrothermal explosion. At the time of the eruption there was no operational geochemical surveillance program. In order to contribute to the strengthening of this program, the Disaster Mitigation Research Center of Nagoya University and the Volcanological Institute of Canary Islands started a collaborative program. To do so, an automatic geochemical station was installed at Ontake volcano and a survey of diffuse CO2efflux and other volatiles was carried out at the surface environment of selected areas of the volcano. The station was installed 10.9 km east away from the eruptive vent, where some earthquakes occurred, and consists of a soil radon (Rn) monitor (SARAD RTM-2010-2) able to measure 222Rn and 220Rn activities. Monitoring of radon is an important geochemical tool to forecast earthquakes and volcanic eruptions due to its geochemical properties. Rn ascends from the lower to the upper part of earth's crust mainly through cracks or faults and its transport needs the existence of a naturally occurring flux of a carrier gas. Regarding to the soil gas survey, it was carried out in August 2016 with 183 measurement points performed in an area of 136 km2. Measurements of soil CO2 efflux were carried out following the accumulation chamber method by means of a portable soil CO2 efflux instrument. To estimate the total CO2 output, sequential Gaussian simulation (sGs) was used allowing the interpolation of the measured variable at not-sampled sites and assess the uncertainly of the total diffuse emission of carbon dioxide estimated for the entire studied area

  18. A complexity measure based method for studying the dependance of 222Rn concentration time series on indoor air temperature and humidity.

    PubMed

    Mihailovic, D T; Udovičić, V; Krmar, M; Arsenić, I

    2014-02-01

    We have suggested a complexity measure based method for studying the dependence of measured (222)Rn concentration time series on indoor air temperature and humidity. This method is based on the Kolmogorov complexity (KL). We have introduced (i) the sequence of the KL, (ii) the Kolmogorov complexity highest value in the sequence (KLM) and (iii) the KL of the product of time series. The noticed loss of the KLM complexity of (222)Rn concentration time series can be attributed to the indoor air humidity that keeps the radon daughters in air.

  19. Radiological impact of phosphogypsum discharged into the Venice lagoon: 222Rn

    NASA Astrophysics Data System (ADS)

    Cantaluppi, C.; Ceccotto, F.; Cianchi, A.; Fasson, A.; Degetto, S.

    2012-04-01

    For about 20 years, between the 60 's and the 80 's of the last century, in the Passo a Campalto area (Lagoon of Venice - Italy) about 400,000 m3 of phosphogypsum (PG) were deposited at the border of the lagoon and next to urban areas without any environmental control. These materials are a by-product formed during the wet processing of phosphate rocks by sulphuric acid and have a significant environmental impact due to their abundance and their chemical-physical and radiochemical characteristics. The PG contains both chemical elements, which are considered dangerous for the ecosystems and natural radionuclides whose concentrations are much higher if compared to those typical for the Earth's crust. These discarded materials caused for many years the dispersion of radionuclides in the environment due to the tidal erosion, the re-suspension of radioactive inhalable dusts, the uncontrolled radon exhalation and the bioaccumulation of some radionuclides in the lagoon environment. After a decision of the appointed authorities, the Venice Water Authority (Ministry of Infrastructure and Transport), planned a permanent safety control of the site resulting in the complete isolation of the entire volume of contaminated materials from the environmental system. The entire project was specific for the particular features of the site and it required the improvement of analytical, sampling and measurement techniques in order to verify the effectiveness of the safety action. The radon assessment, in particular the check of the effectiveness of the inhibition of radon exhalation, is part of a more complex study, covering many other aspects of the management of a permanent disposal; they will be the object of further notes. The ultimate results of this study prove the efficacy of the intervention: radon concentrations in air and exhalation values from the restored area, measured during surveys, have been proved to be well in agreement with those of non contaminated soils.

  20. Removal and deposition efficiencies of the long-lived 222Rn daughters during etching of germanium surfaces

    NASA Astrophysics Data System (ADS)

    Zuzel, G.; Wójcik, M.; Majorovits, B.; Lampert, M. O.; Wendling, P.

    2012-06-01

    Removal and deposition efficiencies of the long-lived 222Rn daughters during etching from and onto surfaces of standard and high purity germanium were investigated. The standard etching procedure of Canberra-France used during production of high purity n-type germanium diodes was applied to germanium discs, which have been exposed earlier to a strong radon source for deposition of its progenies. An uncontaminated sample was etched in a solution containing 210Pb, 210Bi and 210Po. All isotopes were measured before and after etching with appropriate detectors. In contrast to copper and stainless steel, they were removed from germanium very efficiently. However, the reverse process was also observed. Considerable amounts of radioactive lead, bismuth and polonium isotopes present initially in the artificially polluted etchant were transferred to the clean high purity surface during processing of the sample.

  1. KEY COMPARISON: BIPM comparison BIPM.RI(II)-K1.Rn-222 of activity measurements of the radionuclide 222Rn

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Bochud, F. O.

    2004-01-01

    Since 2001, a national metrology institute, the Institut de Radiophysique Appliquée (IRA), Switzerland, has submitted two samples of known activity of 222Rn to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM). The activities ranged from about 13 kBq to 370 kBq. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), with comparison identifier BIPM.RI(II)-K1.Rn-222, according to the provisions of the Mutual Recognition Arrangement (MRA).

  2. Inhalation exposures due to radon and thoron ((222)Rn and (220)Rn): Do they differ in high and normal background radiation areas in India?

    PubMed

    Mishra, Rosaline; Sapra, B K; Prajith, R; Rout, R P; Jalaluddin, S; Mayya, Y S

    2015-09-01

    In India, High Background Radiation Areas (HBRAs) due to enhanced levels of naturally occurring radionuclides in soil (thorium and, to a lesser extent, uranium), are located along some parts of the coastal tracts viz. the coastal belt of Kerala, Tamilnadu and Odisha. It is conjectured that these deposits will result in higher emissions of radon isotopes ((222)Rn and (220)Rn) and their daughter products as compared to Normal Background Radiation Areas (NBRAs). While the annual external dose rates contributed by gamma radiations in these areas are about 5-10 times higher, the extent of increase in the inhalation dose rates attributable to (222)Rn and (220)Rn and their decay products is not well quantified. Towards this, systematic indoor surveys were conducted wherein simultaneous measurements of time integrated (222)Rn and (220)Rn gas and their decay product concentrations was carried out in around 800 houses in the HBRAs of Kerala and Odisha to estimate the inhalation doses. All gas measurements were carried out using pin-hole cup dosimeters while the progeny measurements were with samplers and systems based on the Direct radon/thoron Progeny sensors (DRPS/DTPS). To corroborate these passive measurements of decay products concentrations, active sampling was also carried out in a few houses. The results of the surveys provide a strong evidence to conclude that the inhalation doses due to (222)Rn and (220)Rn gas and their decay products in these HBRAs are in the same range as observed in the NBRAs in India.

  3. Chemical fertilizers as a source of (238)U, (40)K, (226)Ra, (222)Rn, and trace metal pollutant of the environment in Saudi Arabia.

    PubMed

    Alshahri, Fatimh; Alqahtani, Muna

    2015-06-01

    The specific activities of (238)U, (226)Ra, (40)K, and (222)Rn in chemical fertilizers were measured using gamma ray spectrometer and Cr-39 detector. In this study, 21 chemical fertilizers were collected from Eastern Saudi Arabian markets. The specific activities of (238)U ranged from 23 ± 0.5 to 3900 ± 195 Bq kg(-1); (226)Ra ranged from 5.60 ± 2.80 to 392 ± 18 Bq kg(-1); and (40)K ranged from 18.4 ± 3 to 16,476 ± 820 Bq kg(-1). The radon concentrations and the radon exhalation rates were found to vary from 3.20 ± 1.20 to 1532 ± 160 Bq m(-3) and from 1.60 to 774 mBq m(-2) h(-1), respectively. Radium equivalent activities (Raeq) were calculated for the analyzed samples to assess the radiation hazards arising due to the use of these chemical fertilizers in the agriculture soil. The Raeq for six local samples (nitrogen, phosphorous, and potassium (NPK) and single superphosphate (SSP)) and one imported sample (Sulfate of Potash (SOP)) were greater than the acceptable value 370 Bq kg(-1). The total air absorbed doses rates in air 1 m above the ground (D) were calculated for all samples. All samples, except one imported granule sample diammonium phosphate (DAP), were higher than the estimated average global terrestrial radiation of 55 nGy h(-1). The highest annual effective dose was in triple super phosphate (TSP) fertilizers (2.1 mSv y(-1)). The results show that the local TSP, imported SOP, and local NPK (sample 13) fertilizers were unacceptable for use as fertilizers in agricultural soil. Furthermore, the toxic elements and trace metals (Pb, Cd, Cr, Co, Ni, Hg, and As) were determined using atomic absorption spectrometer. The concentrations of chromium in chemical fertilizers were higher than the global values.

  4. Radon mapping, automatic measurements and extremely high 222Rn emissions during the 2002-2007 eruptive scenarios at Stromboli volcano

    NASA Astrophysics Data System (ADS)

    Cigolini, C.; Laiolo, M.; Ulivieri, G.; Coppola, D.; Ripepe, M.

    2013-08-01

    We report additional radon data collected at Stromboli during 2002-2007. The whole data set of periodic measurements has been systematically analyzed to retrieve the values of background, threshold and anomaly for all the stations of the network. Maps of radon concentrations in space and time correlate with changes in volcanic activity. Higher radon emissions are essentially concentrated at summit stations and may also affect some stations located onto the summit-eastern sector of the cone (along the N60°E fracture zone), as well as two stations placed at the NE edge of Sciara del Fuoco. Most of these stations are well above their threshold values during effusive eruptions (namely 2002-2003 and 2007) due to the progressive structural adjustment of the volcano edifice coupled with the opening and resetting of the fracture network. A two-year-long timeseries of automatic 222Rn measurements (2005-2007) was analyzed together with local environmental parameters and selected geophysical data (on seismic tremor and infrasonic puffing). The data show good correlation between radon and the latter parameters particularly during periods of high Strombolian activity (March-April 2006), and before the onset of the February 27, 2007 lava effusion (with radon emissions being well above 20,000 Bq/m3). Extremely high radon emissions (up to ~ 1.7 × 106 Bq/m3) were recorded along the fractures of the SW crater during the first two months of the 2002-2003 effusive eruption. Very high radon emissions (up to ~ 470,000 Bq/m3 for 222Rn, and ~ 780,000 Bq/m3 for 220Rn, respectively) were also detected by the automatic measurements at the summit station during June 20-early July 2007: i.e., just prior to the resuming of the Strombolian activity at summit craters. These data give us the opportunity to estimate the relative depths of the summit fractures during fracturing (being constrained between 200 and 310 m). This is in good agreement with the hypocentral depths of the so called

  5. Estimating the input of submarine groundwater discharge (SGD) and SGD-derived nutrients in Geoje Bay, Korea using (222)Rn-Si mass balance model.

    PubMed

    Hwang, Dong-Woon; Lee, In-Seok; Choi, Minkyu; Kim, Tae-Hoon

    2016-09-15

    In order to evaluate the main source of nutrients for maintaining the high production in shellfish farming bay, we have measured (222)Rn activities and the concentrations of nutrients in stream water, seawater, and coastal groundwater around Geoje Bay, one of the largest cultivation areas of oyster in the southern sea of Korea in April 2013. Using the (222)Rn and Si mass balance model, the residence time of bay seawater was about 5days and the submarine groundwater discharge (SGD) into the bay was estimated to be approximately 1.8×10(6)m(3) d(-1). The SGD-derived nutrient fluxes contributed approximately 54% for DIN, 5% for DIP, and 50% for DSi of total nutrient input entering into the bay. Thus, our results suggest that SGD is the major source of nutrients in Geoje Bay, and SGD-derived nutrients are very important to support the biological production of this shellfish farming bay.

  6. Tracing the sources of gaseous components (222Rn, CO2 and its carbon isotopes) in soil air under a cool-deciduous stand in Sapporo, Japan.

    PubMed

    Fujiyoshi, Ryoko; Haraki, Yukihide; Sumiyoshi, Takashi; Amano, Hikaru; Kobal, Ivan; Vaupotic, Janja

    2010-02-01

    Radon ((222)Rn) and carbon dioxide were monitored simultaneously in soil air under a cool-temperate deciduous stand on the campus of Hokkaido University, Sapporo, Japan. Both (222)Rn and CO(2) concentrations in soil air varied with atmospheric (soil) temperature in three seasons, except for winter when the temperature in soil air remained constant at 2-3 degrees C at depth of 80 cm. In winter, the gaseous components were influenced by low-pressure region passing through the observation site when the ground surface was covered with snow of ~1 m thickness. Carbon isotopic analyses of CO(2) suggested that CO(2) in soil air may result from mixing of atmospheric air and soil components of different origins, i.e. CO(2) from contemporary soil organic matter and old carbon from deeper source, to varying degrees, depending on seasonal meteorological and thus biological conditions.

  7. Gas exchange dependency on diffusion coefficient: direct /sup 222/Rn and /sup 3/He comparisons in a small lake

    SciTech Connect

    Torgersen, T.; Mathieu, G.; Hesslein, R.H.; Broecker, W.S.

    1982-01-20

    A direct field comparison was conducted to determine the dependency of gas exchange coefficient (k/sub x/) on the diffusion coefficient (D/sub x/). The study also sought to confirm the enhanced vertical exchange properties of limnocorrals and similar enclosures. Gas exchange coefficients for /sup 222/Rn and /sup 3/He were determined in a small northern Ontario lake, using a /sup 226/Ra and /sup 3/H spike to gain the necessary precision. The results indicate that the gas exchange coefficient is functionally dependent on the diffusion coefficient raised to the 1.22/sub -35//sup + > 12/ power (k/sub x/ = f(D/sub x//sup 1.22)), clearly supporting the stagnant film model of gas exchange. Limnocorrals were found to have gas exchange rates up to 1.7 times higher than the whole lake in spite of the observation of more calm surface conditions in the corral than in the open lake. 33 references, 6 figures, 8 tables.

  8. Outdoor 220Rn, 222Rn and terrestrial gamma radiation levels: investigation study in the thorium rich Fen Complex, Norway.

    PubMed

    Mrdakovic Popic, Jelena; Bhatt, Chhavi Raj; Salbu, Brit; Skipperud, Lindis

    2012-01-01

    The present study was done in the Fen Complex, a Norwegian area rich in naturally occurring radionuclides, especially in thorium ((232)Th). Measurement of radioactivity levels was conducted at the decommissioned iron (Fe) and niobium (Nb) mining sites (TENORM) as well as at the undisturbed wooded sites (NORM), all open for free public access. The soil activity concentrations of (232)Th (3280-8395 Bq kg(-1)) were significantly higher than the world and the Norwegian average values and exceeded the Norwegian screening level (1000 Bq kg(-1)) for radioactive waste, while radium ((226)Ra) was present at slightly elevated levels (89-171 Bq kg(-1)). Terrestrial gamma dose rates were also elevated, ranging 2.6-4.4 μGy h(-1). Based on long-term surveys, the air concentrations of thoron ((220)Rn) and radon ((222)Rn) reached 1786 and 82 Bq m(-3), respectively. Seasonal variation in the outdoor gamma dose rates and Rn concentrations was confirmed. Correlation analyses showed a linear relationship between air radiation levels and the abundance of (232)Th in soil. The annual outdoor effective radiation doses for humans (occupancy 5 h day(-1)) were estimated to be in the range of 3.0-7.7 mSv, comparable or higher than the total average (summarized indoor and outdoor) exposure dose for the Norwegian population (2.9 mSv year(-1)). On the basis of all obtained results, this Norwegian area should be considered as enhanced natural radiation area (ENRA).

  9. Investigations of a specific surface area of a material on the basis of /sup 222/Rn emanation coefficient measurements

    SciTech Connect

    Morawska, L.

    1989-07-01

    A theoretical model of Rn emanation by a crystal lattice into the pore space of a material is presented. This model makes it possible to calculate the pore emanation rate of a material. Measurements of the /sup 222/Rn emanation coefficient of lightweight concrete for different grain sizes were performed. Using the results of the measurements and the calculated value of a pore emanation rate, a specific surface area of the material was determined. For non-ground lightweight concrete, this value is (1.40 +/- 0.13) x 10(4) cm2 g-1. It is shown that grinding to grain sizes below 60 microns is required to cause a significant increase of specific surface area and thus of the emanation coefficient. However, these results should be treated only as an estimation because the analysis does not account for the real structure of the lightweight concrete. The aim of this work is to present the possibility of connecting the theoretical calculations with the results of measurements in order to determine the specific surface area of a material.

  10. Investigations of a specific surface area of a material on the basis of 222Rn emanation coefficient measurements.

    PubMed

    Morawska, L

    1989-07-01

    A theoretical model of Rn emanation by a crystal lattice into the pore space of a material is presented. This model makes it possible to calculate the pore emanation rate of a material. Measurements of the 222Rn emanation coefficient of lightweight concrete for different grain sizes were performed. Using the results of the measurements and the calculated value of a pore emanation rate, a specific surface area of the material was determined. For non-ground lightweight concrete, this value is (1.40 +/- 0.13) x 10(4) cm2 g-1. It is shown that grinding to grain sizes below 60 microns is required to cause a significant increase of specific surface area and thus of the emanation coefficient. However, these results should be treated only as an estimation because the analysis does not account for the real structure of the lightweight concrete. The aim of this work is to present the possibility of connecting the theoretical calculations with the results of measurements in order to determine the specific surface area of a material.

  11. Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

    NASA Astrophysics Data System (ADS)

    Kumar, K. Charan; Prasad, T. Rajendra; Ratnam, M. Venkat; Nagaraja, Kamsali

    2016-10-01

    Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth's surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon ( R = - 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m-3 and 4.25±0.18 Bq m-3 for its progenies, in the study period.

  12. Assessment of submarine groundwater discharge and associated dissolved inorganic carbon into a coastal wetland, western Taiwan via time-series observations of 222Rn

    NASA Astrophysics Data System (ADS)

    Hsu, Feng-Hsin; Su, Chih-Chieh; Wang, Pei-Ling

    2017-04-01

    We investigated submarine groundwater discharge (SGD) and associated dissolved inorganic carbon flux into the Gaomei wetland, which is located south of the Tachia river's mouth, western Taiwan. This area is characterized by a great tidal range (over 3 m at spring tide) and a shallow unconfined aquifer (˜2 m below the seafloor) with high groundwater recharging rates (over 500 mm yr-1) in the hinterland. In this study we argue that in the Gaomei wetland, tidal pumping causes an exchanging between groundwater and seawater, resulting in an overall dissolved inorganic carbon (DIC) flux into the wetland. Time-series observations of 222Rn were conducted over 2 tidal cycles in both dry (May of 2014) and wet seasons (August of 2014) seasons at a station 500 m offshore. Our result shows a good response to tidal fluctuation with higher 222Rn activities at low tide and lower 222Rn activities at high tide. Based on a 222Rn mass balance model taking all sources and sinks into account, we estimated a SGD flux ranging from -3.86 to 69 cm d-1 with slightly higher fluxes during the wet season (average SGD flux 22 cm d-1) compared to the dry season (average SGD flux 16 cm d-1). Our negative SGD flux estimates observed during high tides suggest that seawater infiltrates into the sediments during flood tide and discharges during ebb tide, proving the concept of seawater exchange across the water-sediment interface. The overall SGD-borne DIC fluxes range between 1.82×106 and 2.48×106 mol d-1 in dry and wet seasons, respectively, that are 26 % and 36 % of the river-induced DIC fluxes. Such an export of DIC flux from the groundwater (or recycled seawater) might have an impact on coastal biogeochemistry in the Gaomei wetland.

  13. An International Marine-Atmospheric 222Rn Measurement Intercomparison in Bermuda Part I: NIST Calibration and Methodology for Standardized Sample Additions

    PubMed Central

    Collé, R.; Unterweger, M. P.; Hodge, P. A.; Hutchinson, J. M. R.

    1996-01-01

    As part of an international 222Rn measurement intercomparison conducted at Bermuda in October 1991, NIST provided standardized sample additions of known, but undisclosed (“blind”) 222Rn concentrations that could be related to U.S. national standards. The standardized sample additions were obtained with a calibrated 226Ra source and a specially-designed manifold used to obtain well-known dilution factors from simultaneous flow-rate measurements. The additions were introduced over sampling periods of several hours (typically 4 h) into a common streamline on a sampling tower used by the participating laboratories for their measurements. The standardized 222Rn activity concentrations for the intercomparison ranged from approximately 2.5 Bq · m−3 to 35 Bq · m−3 (of which the lower end of this range approached concentration levels for ambient Bermudian air) and had overall uncertainties, approximating a 3 standard deviation uncertainty interval, of about 6 % to 13 %. This paper describes the calibration and methodology for the standardized sample additions. PMID:27805090

  14. Testing the usefulness of (222)Rn to complement conventional hydrochemical data to trace groundwater provenance in complex multi-layered aquifers. Application to the Úbeda aquifer system (Jaén, SE Spain).

    PubMed

    Ortega, L; Manzano, M; Rodríguez-Arévalo, J

    2017-12-01

    The Úbeda aquifer system is a multi-layered aquifer intensively exploited for irrigation. It covers 1100km(2) and consists of piled up sedimentary aquifer and aquitard layers from Triassic sandstones and clays at the bottom, to Jurassic carbonates (main exploited layer) in the middle, and Miocene sandstones and marls at the top. Flow network modification by intense exploitation and the existence of deep faults favour vertical mixing of waters from different layers and with distinct chemical composition. This induces quality loss and fosters risk of quantity restrictions. To support future groundwater abstraction management, a hydrogeochemical (major and some minor solutes) and isotopic ((222)Rn) study was performed to identify the chemical signatures of the different layers and their mixing proportions in mixed samples. The study of 134 groundwater samples allowed a preliminary identification of hydrochemical signatures and mixtures, but the existence of reducing conditions in the most exploited sector prevents the utility of sulphate as a tracer of Triassic groundwater in the Jurassic boreholes. The potential of (222)Rn to establish isotopic signatures and to trace groundwater provenance in mixtures was tested. (222)Rn was measured in 48 samples from springs and boreholes in most aquifer layers. At first, clear correlations were observed between (222)Rn, Cl and SO4 in groundwater. Afterwards, very good correlations were observed between (222)Rn and the chemical facies of the different layers established with End Member Mixing Analysis (EMMA). Using (222)Rn as part of the signatures, EMMA helped to identify end-member samples, and to quantify the mixing proportions of water from the Triassic and the Deep Miocene layers in groundwater pumped by deep agricultural wells screened in the Jurassic. The incorporation of (222)Rn to the study also allowed identifying the impact of irrigation returns through the association of moderate NO3, Cl, and Br contents with very low

  15. Quantification of submarine groundwater discharge and its short-term dynamics by linking time-variant end-member mixing analysis and isotope mass balancing (222-Rn)

    NASA Astrophysics Data System (ADS)

    Petermann, Eric; Knöller, Kay; Stollberg, Reiner; Scholten, Jan; Rocha, Carlos; Weiß, Holger; Schubert, Michael

    2017-04-01

    Submarine groundwater discharge (SGD) plays a crucial role for the water quality of coastal waters due to associated fluxes of nutrients, organic compounds and/or heavy-metals. Thus, the quantification of SGD is essential for evaluating the vulnerability of coastal water bodies with regard to groundwater pollution as well as for understanding the matter cycles of the connected water bodies. Here, we present a scientific approach for quantifying discharge of fresh groundwater (GWf) and recirculated seawater (SWrec), including its short-term temporal dynamics, into the tide-affected Knysna estuary, South Africa. For a time-variant end-member mixing analysis we conducted time-series observations of radon (222Rn) and salinity within the estuary over two tidal cycles in combination with estimates of the related end-members for seawater, river water, GWf and SWrec. The mixing analysis was treated as constrained optimization problem for finding an end-member mixing ratio that simultaneously fits the observed data for radon and salinity best for every time-step. Uncertainty of each mixing ratio was quantified by Monte Carlo simulations of the optimization procedure considering uncertainty in end-member characterization. Results reveal the highest GWf and SWrec fraction in the estuary during peak low tide with averages of 0.8 % and 1.4 %, respectively. Further, we calculated a radon mass balance that revealed a daily radon flux of 4.8 * 108 Bq into the estuary equivalent to a GWf discharge of 29.000 m3/d (9.000-59.000 m3/d for 25th-75th percentile range) and a SWrec discharge of 80.000 m3/d (45.000-130.000 m3/d for 25th-75th percentile range). The uncertainty of SGD reflects the end-member uncertainty, i.e. the spatial heterogeneity of groundwater composition. The presented approach allows the calculation of mixing ratios of multiple uncertain end-members for time-series measurements of multiple parameters. Linking these results with a tracer mass balance allows conversion

  16. DNA damage in oral epithelial cells of individuals chronically exposed to indoor radon ((222)Rn) in a hydrothermal area.

    PubMed

    Linhares, Diana Paula Silva; Garcia, Patrícia Ventura; Silva, Catarina; Barroso, Joana; Kazachkova, Nadya; Pereira, Rui; Lima, Manuela; Camarinho, Ricardo; Ferreira, Teresa; Dos Santos Rodrigues, Armindo

    2016-11-09

    Hydrothermal areas are potentially hazardous to humans as volcanic gases such as radon ((222)Rn) are continuously released from soil diffuse degassing. Exposure to radon is estimated to be the second leading cause of lung cancer, but little is known about radon health-associated risks in hydrothermal regions. This cross-sectional study was designed to evaluate the DNA damage in the buccal epithelial cells of individuals chronically exposed to indoor radon in a volcanic area (Furnas volcano, Azores, Portugal) with a hydrothermal system. Buccal epithelial cells were collected from 33 individuals inhabiting the hydrothermal area (Ribeira Quente village) and from 49 individuals inhabiting a non-hydrothermal area (Ponta Delgada city). Indoor radon was measured with Ramon 2.2 detectors. Chromosome damage was measured by micronucleus cytome assay, and RAPD-PCR was used as a complementary tool to evaluate DNA damage, using three 10-mer primers (D11, F1 and F12). Indoor radon concentration correlated positively with the frequency of micronucleated cells (r s = 0.325, p = 0.003). Exposure to radon is a risk factor for the occurrence micronucleated cells in the inhabitants of the hydrothermal area (RR = 1.71; 95% CI, 1.2-2.4; p = 0.003). One RAPD-PCR primer (F12) produced differences in the banding pattern, a fact that can indicate its potential for detecting radon-induced specific genomic alterations. The observed association between chronic exposure to indoor radon and the occurrence of chromosome damage in human oral epithelial cells evidences the usefulness of biological surveillance to assess mutations involved in pre-carcinogenesis in hydrothermal areas, reinforcing the need for further studies with human populations living in these areas.

  17. Time variations of 222Rn concentration and air exchange rates in a Hungarian cave.

    PubMed

    Nagy, Hedvig Éva; Szabó, Zsuzsanna; Jordán, Gyozo; Szabó, Csaba; Horváth, Akos; Kiss, Attila

    2012-09-01

    A long-term radon concentration monitoring was carried out in the Pál-völgy cave, Budapest, Hungary, for 1.5 years. Our major goal was to determine the time dependence of the radon concentration in the cave to characterise the air exchange and define the most important environmental parameters that influence the radon concentration inside the cave. The radon concentration in the cave air was measured continuously by an AlphaGuard radon monitor, and meteorological parameters outside the cave were collected simultaneously. The air's radon concentration in the cave varied between 104 and 7776 Bq m(-3), the annual average value was 1884±85 Bq m(-3). The summer to winter radon concentration ratio was as high as 21.8. The outside air temperature showed the strongest correlation with the radon concentration in the cave, the correlation coefficient (R) was 0.76.

  18. Urinary leukotriene E4/exhaled nitric oxide ratio and montelukast response in childhood asthma.

    PubMed

    Rabinovitch, Nathan; Graber, Nora J; Chinchilli, Vernon M; Sorkness, Christine A; Zeiger, Robert S; Strunk, Robert C; Bacharier, Leonard B; Martinez, Fernando D; Szefler, Stanley J

    2010-09-01

    A subset of children with asthma respond better to leukotriene receptor antagonists than to inhaled corticosteroids. Information is needed to identify children with these preferential responses. We sought to determine whether the ratio of urinary leukotriene E(4) (LTE(4)) to fractional exhaled nitric oxide (FE(NO)) delineates children with preferential responsiveness to montelukast compared with fluticasone propionate (FP) therapy. Data from 318 children with mild-to-moderate asthma enrolled in 2 National Heart, Lung, and Blood Institute Childhood Asthma Research and Education Network studies (Characterizing the Response to a Leukotriene Receptor Antagonist and an Inhaled Corticosteroid [CLIC] and the Pediatric Asthma Controller Trial [PACT]) were analyzed. The association between LTE(4)/FE(NO) ratios at baseline and improved lung function or asthma control days (ACDs) with montelukast and FP therapy was determined, and phenotypic characteristics related to high ratios were assessed. LTE(4)/FE(NO) ratios were associated with a greater response to montelukast than FP therapy for FEV(1) measurements (2.1% increase per doubling of ratio, P = .001) and for ACDs per week (0.3-ACD increase, P = .009) in the CLIC study. In PACT the ratio was associated with greater ACD responsiveness to MT than FP therapy (0.6 ACD increase, P=.03) [corrected]. In a combined study analysis, LTE(4): FE(NO) ratios were associated with greater response to MT than FP therapy for FEV(1) (1.8% increase, P =.0005) and ACDs (0.4 increase, P =.001)[corrected].Children with LTE(4)/FE(NO) ratios at or above the 75th percentile were likely (P < .05) to be younger and female and exhibit lower levels of atopic markers and methacholine reactivity. LTE(4)/FE(NO) ratios predict a better response to montelukast than FP therapy in children with mild-to-moderate asthma. Copyright (C) 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  19. Uranium distribution and radon exhalation from Brazilian dimension stones.

    PubMed

    Amaral, P G Q; Galembeck, T M B; Bonotto, D M; Artur, A C

    2012-04-01

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espírito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of (222)Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the (222)Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit.

  20. Natural radioactivity and radon exhalation rates in man-made tiles used as building materials in Japan.

    PubMed

    Iwaoka, K; Hosoda, M; Suwankot, N; Omori, Y; Ishikawa, T; Yonehara, H; Tokonami, S

    2015-11-01

    Man-made tiles frequently used in Japan were collected, and activity concentrations and radon ((222)Rn) exhalation rates in these tiles were measured. Dose estimations for inhabitants living in houses built using these tiles were also carried out. The activity concentrations of (226)Ra, (228)Ra and (40)K in the man-made tiles were 31-170, 35-110 and 260-980 Bq kg(-1), respectively. The (222)Rn exhalation rates in the tiles were 8.8-21 μBq m(-2) s(-1). The ranges of experimental activity concentrations and (222)Rn exhalation rates were almost identical to those of natural rocks used as typical building materials in Japan. The maximum value of effective dose to inhabitants living in houses built with the man-made tiles was 0.14 mSv y(-1), which is lower than the reference level range (1-20 mSv y(-1)) for abnormally high levels of natural background radiation published in the ICRP Publication 103.

  1. A novel silicon diffusion membrane method for high-resolution continuous quantification of groundwater-surface water interaction using 222Rn

    NASA Astrophysics Data System (ADS)

    Cartwright, I.; Hofmann, H.; Gilfedder, B.

    2011-12-01

    222Rn is a naturally produced radioactive isotopic tracer that is commonly used to quantify groundwater discharge to streams, rivers, and wetlands. Traditional sampling and analysis techniques are usually confined to point measurements taken at a specific time. However, it is difficult to constrain short- or medium-term processes occurring at the groundwater-surface water interface using single measurements. Here we describe a method for high-resolution, autonomous, and continuous, measurement of radon in rivers and streams using a silicon diffusion membrane system coupled to a solid state radon-in-air detector (Durridge RAD7). In this system, water is pumped through a silicon diffusion tube placed inside an outer air circuit tube that is connected to the radon-in-air detector. Radon diffuses from the water into the air loop and is measured by the detector. By optimising the membrane tube length, wall thickness, and water flow rates through the membrane, it was possible to quantify the variability of 222Rn concentrations over timescales of about 3 hours and qualitatively observe changes in as little as 20 minutes. The detection limit for the entire system with 20 minutes counting was 0.018 Bq/L at the 3σ level, which is solely determined by the sensitivity of the detector. Results from the diffusion membrane agree well with conventional measurements of 222Rn made using a RAD7 and an air-water exchanger at both high (20 Bq/L) and low (<1 Bq/L) concentrations. The silicon membrane system is suitable for continuous and autonomous monitoring of groundwater-surface water interactions on hourly to monthly times scales. Unlike unshielded diffusion membranes (such as the Membrana system), the system is not prone to clogging with sediment or biofilms even in turbid water; additionally, the silicon membrane is flexible and can be coiled for installation at sites where space is restricted. While the response times are slower than air-water exchangers, the silicon membrane

  2. Determination of 222Rn in fresh water: development of a robust method of analysis by alpha/beta separation liquid scintillation spectrometry.

    PubMed

    Pates, Jacqueline M; Mullinger, Neil J

    2007-01-01

    Liquid scintillation spectrometry is used widely for determining (222)Rn in natural waters; however, the benefits of alpha/beta separation have not been fully explored. The extractants toluene and Ultima Gold F were compared, and both performed well for a range of extreme waters. A robust method for calibrating extraction and counting efficiencies has been developed. Detection limits are 20 mBql(-1) (toluene) and 16 mBql(-1) (UGF) for a 60 min count and 600-ml sample, halving the required sample volume.

  3. Evaluating the accuracy of core incubations to determine benthic fluxes of 222Rn, 228Ra, and 224Ra, measured in core incubations

    NASA Astrophysics Data System (ADS)

    Wolfe, C. I.; Hammond, D. E.; Schwartz, R. J.

    2009-12-01

    Profiles of radioisotopes in bottom waters are often used to estimate vertical transport. However, horizontal transport often plays a role and may be difficult to evaluate. A boundary condition useful for constraining transport rates is to establish the isotope flux from benthic sediments. We tested a new method to estimate benthic fluxes of isotopes by incubating sediment cores from San Pedro Basin and measuring the changes in concentrations of 222Rn, 228Ra and 224Ra in the overlying water, over a six to seven day incubation period. These results have been compared to fluxes established by applying diffusion-reaction models to the sediment column, based on measuring isotope emanation from sediments, adsorption coefficients, and profiles of the parent isotopes in sediments. There was internal consistency (± 30%) between the core incubation measurement and the radon emanation flux calculated from diffusion-reaction models. The 224Ra flux measurements have been complicated by minor disturbances of cores during collection and the removal of its 228Th parent from core top water during incubation. The 228Ra measurements from San Pedro cores are still in progress, as they require a six month ingrowth period. Cores obtained from Cascadia Basin have also been incubated for two to four days. Incubation fluxes of 222Rn are consistent with the standing crop observed in bottom waters. Incubation fluxes of 228Ra are consistent with predictions from modeling solid phase profiles of radioisotopes in sediments.

  4. Radon surveys and real-time monitoring at Stromboli volcano: Influence of soil temperature, atmospheric pressure and tidal forces on 222Rn degassing

    NASA Astrophysics Data System (ADS)

    Cigolini, C.; Poggi, P.; Ripepe, M.; Laiolo, M.; Ciamberlini, C.; Delle Donne, D.; Ulivieri, G.; Coppola, D.; Lacanna, G.; Marchetti, E.; Piscopo, D.; Genco, R.

    2009-07-01

    We used a network of stations to perform systematic radon surveys at Stromboli volcano. The time series of periodic measurements show that monthly average 222Rn emissions reflect changes in volcanic activity and exhibit increasing trends prior and during the last major eruptive cycles. Maps of radon emissions indicate that diffuse degassing is operative at Stromboli volcano. Concentrated degassing essentially occurs in the summit area and within a sector proximal to the two major NE trending faults. These sites were chosen for deploying the two real-time stations that are currently operating at Stromboli. In these devices, the 222Rn electronic dosimeters are connected to a radiomodem for wireless data transfer to a receiving station at the volcano observatory. Radon activity, soil temperature and atmospheric pressure data are sampled and instantaneously transferred via web so that they can be checked remotely. Collected time series reveal an overall inverse correlation between radon emissions and seasonal temperature variations. Radon emissions in sectors of diffuse degassing are modulated by tidal forces as well. Radon activities recorded at the summit station, located along the fracture zone where the gas flux is concentrated, are positively correlated with changes in atmospheric pressure and confirm the occurrence of the "atmospheric stack effect". We finally emphasize that real-time radon monitoring is an innovative technique that may be systematically applied in volcano surveillance.

  5. LASER BIOLOGY AND MEDICINE: Laser analysis of the 13C/12C isotope ratio in CO2 in exhaled air

    NASA Astrophysics Data System (ADS)

    Stepanov, E. V.

    2002-11-01

    Tunable diode lasers (TDLs) are applied to the diagnostics of gastroenterological diseases using respiratory tests and preparations enriched with the stable 13C isotope. This method of the analysis of the 13C/12C isotope ratio in CO2 in exhaled air is based on the selective measurement of the resonance absorption at the vibrational — rotational structure of 12CO2 and 13CO2. The CO2 transmission spectra in the region of 4.35 μm were measured with a PbEuSe double-heterostructure TDL. The accuracy of carbon isotope ratio measurements in CO2 of exhaled air performed with the TDL was ~0.5%. The data of clinical tests of the developed laser-based analyser are presented.

  6. Radon exhalation from phosphogypsum building boards: symmetry constraints, impermeable boundary conditions and numerical simulation of a test case.

    PubMed

    Rabi, J A; da Silva, Nivaldo C

    2006-01-01

    Comprehensive understanding of (222)Rn exhalation from phosphogypsum-bearing building material and its accumulation in indoor air is likely to rely on numerical simulation, particularly if transient effects, three-dimensional domains and convection are to be included and investigated. Yet, experimental data and analytical results are helpful (if not crucial) as far as validation is concerned. Having in mind computational code simplicity and in the light of a recent experimental and theoretical report on (222)Rn release from phosphogypsum boards for housing panels, this paper presents and discusses an alternative testing set-up and the corresponding boundary conditions, namely one side of the panel bounded by impermeable wall. Although this is a new facility to be tested, the resultant steady-state one-dimensional diffusion-dominant analytical solution is shown to match the counterpart deduced in the aforementioned previous report, despite it relaxes the constraint of symmetry about the phosphogypsum board centerline, which is inferred in that prior experimental scenario. In addition, numerical results are conducted for a diffusion-dominant two-dimensional time-varying test case concerning (222)Rn accumulation in a closed chamber having an exhaling phosphogypsum board tightly placed at one wall.

  7. (222)Rn activity concentration differences in groundwaters of three Variscan granitoid massifs in the Sudetes (NE Bohemian Massif, SW Poland).

    PubMed

    Przylibski, Tadeusz A; Gorecka, Joanna

    2014-08-01

    Based on research conducted in three Variscan granitoid massifs located within the crystalline Bohemian Massif, the authors confirmed that the higher the degree of their erosional dissection, the smaller the concentration of (222)Rn in groundwaters circulating in these massifs. This notion implies that radon waters and high-radon waters, from which at least some of the dissolved radon should be removed before feeding them as drinking water to the water-supply system, could be expected in granitoid massifs which have been poorly exposed by erosion. At the same time, such massifs must be taken into account as the areas of possible occurrence of radon medicinal waters, which in some countries can be used for balneotherapy in health resorts. Slightly eroded granitoid massifs should be also regarded as very probable radon prone areas or areas of high radon potential.

  8. Gas exchange and CO2 flux in the tropical Atlantic Ocean determined from 222Rn and pCO2 measurements

    NASA Astrophysics Data System (ADS)

    Smethie, William M.; Takahashi, Taro; Chipman, David W.; Ledwell, James R.

    1985-01-01

    Measurements of 222Rn vertical profiles and pCO2 in the surface water and the atmosphere were made simultaneously in the tropical Atlantic ocean as part of the TTO/TAS program. The gas exchange rate or piston velocity was determined from the 222Rn profiles, and the ΔpCO2 between the surface ocean and the atmosphere was determiend from the pCO2 measurements. The net flux of CO2 across the sea-air interface was calculated from these two data sets. The piston velocity ranged from 1.4 to 6.9 m/d and was correlated with wind speed. The slope of piston velocity versus wind speed was estimated to be between 0.3 and 1.1 (m/d)/(m/s). The ΔpCO2 ranged from -35 μatm at 15°N, 55°W to +64 /zatm at 5°S, 28°W, with the zero ΔpCO2 isopleth located at about 10°N. The high ΔpCO2 values can be explained by lateral advection of surface water from the east with heating and biological consumption of CO2 and alkalinity during transit. The net flux of CO2 was into the ocean north of 10°N latitude with values reaching a maximum of 1.4 mol m-2 yr-1 at 15°N, 50°W. South of 10°N, the net flux was out of the ocean, reaching a maximum value of 2.7 mol m-2 yr-1 at 8°S, 28°W. The average net flux from 10°N to 10°S was 1.3 mol m-2 yr-1 out of the ocean, which is equivalent to 0.15 gigatons of carbon per year if the flux determined applied throughout the year.

  9. SOIL 222Rn CONCENTRATION, CO2 AND CH4 FLUX MEASUREMENTS AROUND THE JWALAMUKHI AREA OF NORTH-WEST HIMALAYAS, INDIA.

    PubMed

    Kumar, Arvind; Walia, Vivek; Yang, Tsanyao Frank; Fu, Ching-Chou; Singh, Surinder; Bajwa, Bikramjit Singh; Arora, Vishal

    2016-10-01

    Soil (222)Rn concentration, CO2 and CH4 flux measurements were conducted around the Jwalamukhi area of North-West Himalayas, India. During this study, around 37 soil gas points and flux measurements were taken with the aim to assure the suitability of this method in the study of fault zones. For this purpose, RAD 7 (Durridge, USA) was used to monitor radon concentrations, whereas portable diffuse flux meter (West Systems, Italy) was used for the CO2 and CH4 flux measurements. The recorded radon concentration varies from 6.1 to 34.5 kBq m(-3) with an average value of 16.5 kBq m(-3) The anomalous value of radon concentrations was recorded between Jwalamukhi thrust and Barsar thrust. The recorded average of CO2 and CH4 flux were 11.8 and 2.7 g m(-2) day(-1), respectively. The good correlation between anomalous CO2 flux and radon concentrations has been observed along the fault zone in the study area, suggesting that radon migration is dependent on CO2. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. In vivo measurements of 210Pb in skull and knee geometries as an indicator of cumulative 222Rn exposure in a underground coal mine in Brazil.

    PubMed

    Dantas, A L A; Dantas, B M; Lipsztein, J L; Spitz, H B

    2007-01-01

    Cumulative exposure to radon can be evaluated by measuring 210Pb in bone. The skull and knee are two convenient parts of the skeleton for in vivo measuring 210Pb because these regions of the body present a high concentration of bone, the detectors are easily positioned and the likelihood of cross contribution from other organs or tissues is low. A radiological survey of non-uranium mines in Brazil indicated that an underground coal mine in Paraná, located in the south of Brazil, exhibited a high radon concentration. In vivo measurements of 32 underground coal miners were performed in the IRD-CNEN Whole Body Counter shielded room using an array of four high-resolution germanium detectors. Estimations of 210Pb in the total skeleton were determined from direct in vivo measurements of 210Pb in the head and knees. In vivo measurements of 210Pb in 6 out of 32 underground coal miners ranged from 80 to 164 Bq, suggesting that these workers were significantly exposed to 222Rn.

  11. Gas chromatograph-surface acoustic wave for quick real-time assessment of blood/exhaled gas ratio of propofol in humans.

    PubMed

    Chen, X; Zhang, X L; Liu, L; Chen, Y; Piao, M Y; Zhang, F J; Wu, W D; Zhong, Y B; Sun, K; Zou, Y C; Zhang, X; Wang, D; Wang, P; Yan, M

    2014-11-01

    Although pilot studies have reported that exhaled propofol concentrations can reflect intraoperative plasma propofol concentrations in an individual, the blood/exhaled partial pressure ratio RBE varies between patients, and the relevant factors have not yet been clearly addressed. No efficient method has been reported for the quick evaluation of RBE and its association with inter-individual variables. We proposed a novel method that uses a surface acoustic wave (SAW) sensor combined with a fast gas chromatograph (GC) to simultaneously detect propofol concentrations in blood and exhaled gas in 28 patients who were receiving propofol i.v. A two-compartment pharmacokinetic (PK) model was established to simulate propofol concentrations in exhaled gas and blood after a bolus injection. Simulated propofol concentrations for exhaled gas and blood were used in a linear regression model to evaluate RBE. The fast GC-SAW system showed reliability and efficiency for simultaneous quantitative determination of propofol in blood (correlation coefficient R(2)=0.994, P<0.01) and exhaled gas (R(2)=0.991, P<0.01). The evaluation of RBE takes <50 min for a patient. The distribution of RBE in 28 patients showed inter-individual differences in RBE (median 1.27; inter-quartile range 1.07-1.59). Fast GC-SAW, which analyses samples in seconds, can perform both rapid monitoring of exhaled propofol concentrations and fast analysis of blood propofol concentrations. The proposed method allows early determination of the coefficient RBE in individuals. Further studies are required to quantify the distribution of RBE in a larger cohort and assess the effect of other potential factors. ChiCTR-ONC-13003291. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Early results of experimental 222Rn flux campaign carried out at a mountain Spanish region and comparison with available radon flux inventories results

    NASA Astrophysics Data System (ADS)

    Nofuentes, Manel; Grossi, Claudia; Morguí, Josep Anton; Curcoll, Roger; Cañas, Lidia; Occhipinti, Paola; Borràs, Silvia; Vazquez, Eusebi; Rodó, Xavier

    2015-04-01

    The atmospheric concentrations of components impacting the greenhouse effect (CO2, CH4, N2O, O3, and aerosols) have increased significantly in the last two centuries, leading to a direct impact on our climate. These climatic changes deeply affect the geochemistry and the dynamics of the main reservoirs such as the atmosphere, the ocean, and the biosphere. Therefore, reductions of the emissions are needed for all four of the most important anthropogenic GHGs: CO2, CH4, N2O and SF6. Particularly, the relative contribution of human induced CH4 in the atmosphere to the total human direct greenhouse effect is about 25%. Furthermore, the CH4 has the shortest lifetime in the atmosphere (about 9 years), so that emissions reduction measures for CH4 will lead to changes in concentration growth rates, or even a concentration decline, at relatively shor time scales. All these reasons make the CH4 an attractive compound to reduce the greenhouse gas emissions. Nowadays, the study and attribution of categories for GHGs sources is carried out by using bottom-up inventories and top-down techniques. The atmospheric concentrations and the fluxes of the noble and radioactive 222Rn gas are widely used for retriving indirectly GHGs fluxes, improving top-down techniques and analysing different type of sources. In the frame of the "Methane exchange between soil and atmosphere over the Iberian Peninsula" (MIP) project (Reference: CGL2013-46186-R, Spanish Ministry of Economy and Competitiveness) four experimental radon flux campaigns are carried out at mountain as well as at coastal Spanish regions using integrated and continuous monitors. The early results of first radon flux campaign carried out at the Gredos and Iruelas climate station (GIC3) of the Catalan Institute of Climate Science (IC3) are presented and compared with available radon flux inventories maps.

  13. Temporal 222Rn distributions to reveal groundwater discharge into desert lakes: Implication of water balance in the Badain Jaran Desert, China

    NASA Astrophysics Data System (ADS)

    Luo, Xin; Jiao, Jiu Jimmy; Wang, Xu-sheng; Liu, Kun

    2016-03-01

    How lake systems are maintained and water is balanced in the lake areas in the Badain Jaran Desert (BJD), northeast of China have been debated for about a decade. In this study, continuous 222Rn measurement is used to quantify groundwater discharge into two representative fresh and brine water lakes in the desert using a steady-state mass-balance model. Two empirical equations are used to calculate atmospheric evasion loss crossing the water-air interface of the lakes. Groundwater discharge rates yielded from the radon mass balance model based on the two empirical equations are well correlated and of almost the same values, confirming the validity of the model. The fresh water and brine lakes have a daily averaged groundwater discharge rate of 7.6 ± 1.7 mm d-1 and 6.4 ± 1.8 mm d-1, respectively. The temporal fluctuations of groundwater discharge show similar patterns to those of the lake water level, suggesting that the lakes are recharged from nearby groundwater. Assuming that all the lakes have the same discharge rate as the two studied lakes, total groundwater discharge into all the lakes in the desert is estimated to be 1.59 × 105 m3 d-1. A conceptual model of water balance within a desert lake catchment is proposed to characterize water behaviors within the catchment. This study sheds lights on the water balance in the BJD and is of significance in sustainable regional water resource utilization in such an ecologically fragile area.

  14. NIST 222Rn emission standards.

    PubMed

    Volkovitsky, Peter

    2006-01-01

    NIST radon standards are hermetically sealed polyethylene capsules filled with 226Ra solution. Recently, four new series of standards with activities 5, 50, 500, and 5000 Bq were prepared. The measured emanation fraction agrees with a calculation that accounts for the radon accumulated inside the polyethylene walls of the capsule. Obtained solubility of radon in polyethylene is approximately 45 of the solubility of radon in water. The radon diffusion coefficient in low-density polyethylene is 7.2x10(-8)cm2/s.

  15. 13CO2/12CO2 ratio analysis in exhaled air by lead-salt tunable diode lasers for noninvasive diagnostics in gastroenterology

    NASA Astrophysics Data System (ADS)

    Stepanov, Eugene V.; Zyrianov, Pavel V.; Miliaev, Valerii A.; Selivanov, Yurii G.; Chizhevskii, Eugene G.; Os'kina, Svetlana; Ivashkin, Vladimir T.; Nikitina, Elena I.

    1999-07-01

    An analyzer of 13CO2/12CO2 ratio in exhaled air based on lead-salt tunable diode lasers is presented. High accuracy of the carbon isotope ratio detection in exhaled carbon dioxide was achieved with help of very simple optical schematics. It was based on the use of MBE laser diodes operating in pulse mode and on recording the resonance CO2 absorption at 4.2 micrometers . Special fast acquisition electronics and software were applied for spectral data collection and processing. Developed laser system was tested in a clinical train aimed to assessment eradication efficiency in therapy of gastritis associated with Helicobacter pylori infection. Data on the 13C-urea breath test used for P.pylori detection and obtained with tunable diode lasers in the course of the trail was compared with the results of Mass-Spectroscopy analysis and histology observations. The analyzer can be used also for 13CO2/12CO2 ratio detection in exhalation to perform gastroenterology breath test based on using other compounds labeled with stable isotopes.

  16. Determination of radon exhalation from construction materials using VOC emission test chambers.

    PubMed

    Richter, M; Jann, O; Kemski, J; Schneider, U; Krocker, C; Hoffmann, B

    2013-10-01

    The inhalation of (222) Rn (radon) decay products is one of the most important reasons for lung cancer after smoking. Stony building materials are an important source of indoor radon. This article describes the determination of the exhalation rate of stony construction materials by the use of commercially available measuring devices in combination with VOC emission test chambers. Five materials - two types of clay brick, clinker brick, light-weight concrete brick, and honeycomb brick - generally used for wall constructions were used for the experiments. Their contribution to real room concentrations was estimated by applying room model parameters given in ISO 16000-9, RP 112, and AgBB. This knowledge can be relevant, if for instance indoor radon concentration is limited by law. The test set-up used here is well suited for application in test laboratories dealing with VOC emission testing.

  17. Development of a technique for the measurement of the radon exhalation rate using an activated charcoal collector.

    PubMed

    Iimoto, Takeshi; Akasaka, Yoshinori; Koike, Yuya; Kosako, Toshiso

    2008-04-01

    A simple system to evaluate the 222Rn (radon) exhalation rate from soil has been improved. A sampling cuvette of 2.1 L is placed so that it covers the targeted ground soil, and radon emanating from the soil accumulates within the cuvette for 24 h. Its internal radon concentration is measured by the combination of an activated charcoal (PICO-RAD) and a liquid scintillation counting system. This study shows variations of the conversion factor (CF: unit Bq m(-3)/cpm) of PICO-RAD. The range of CF due to temperature (10-30 degrees C) was between -21% and +69%, and this due to humidity (30-90%) was between 0% and -15%. Humidity and radon concentration in the cuvette covering soil tended to saturate in a few hours. The above information was used to correct the CF for the evaluation. The improved system shows high reliability and can be easily applied to natural environments.

  18. Development of a model using the MATLAB System identification toolbox to estimate (222)Rn equilibrium factor from CR-39 based passive measurements.

    PubMed

    Abo-Elmagd, M; Sadek, A M

    2014-12-01

    Can and Bare method is a widely used passive method for measuring the equilibrium factor F through the determination of the track density ratio between bare (D) and filtered (Do) detectors. The dimensions of the used diffusion chamber are altering the deposition ratios of Po-isotopes on the chamber walls as well as the ratios of the existing alpha emitters in air. Then the measured filtered track density and therefore the resultant equilibrium factor is changed according to the diffusion chamber dimensions. For this reason, high uncertainty was expected in the measured F using different diffusion chambers. In the present work, F is derived as a function of both track density ratio (D/Do) and the dimensions of the used diffusion chambers (its volume to the total internal surface area; V/A). The accuracy of the derived formula was verified using the black-box modeling technique via the MATLAB System identification toolbox. The results show that the uncertainty of the calculated F by using the derived formula of F (D/Do, V/A) is only 5%. The obtained uncertainty ensures the quality of the derived function to calculate F using diffusion chambers with wide range of dimensions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. [Contents of radon 222Rn in drinking water of Sweradów Zdrój and Czerniawa Zdrój].

    PubMed

    Pachocki, K A; Gorzkowski, B; Wilejczyk, E; Smoter, J

    2000-01-01

    Radon-222 concentration in surface water, wells and tap water in Swieradów Zdrój and in Czerniawa Zdrój has been quantitative determined. The measurements were performed using the alpha liquid scintillation counting method. Radon arithmetic mean for water of individual wells in Swieradów Zdrój was found to be 438.5 Bq/l within the range between 42 Bq/ and 1095 Bq/l. The appropriate mean value for water of individual wells Czerniawa Zdrój was 165 Bq/l within the range from 25.8 Bq/l and 402.4 Bq/l. Waterworks in Czerniawa Zdrój is supplied with the surface water in which the radon concentration is low (about 2 Bq/l). Water works in Swieradów Zdrój is supplied with the mixed water consisting from the surface water, which main characteristic is low radon concentration (below 11 Bq/l), and from artesian well and mine gallery water with the radon concentration from 321 Bq/l to 464 Bq/l in it. This water is mixed in various ratios and therefore the radon concentration in it was within 4 Bq/l and 79 Bq/l.

  20. Monitoring Exhaled Carbon Dioxide.

    PubMed

    Siobal, Mark S

    2016-10-01

    In the past few decades, assessment of exhaled CO2 in both intubated and non-intubated patients has evolved into an essential component in many aspects of patient monitoring. Besides the basic assessment of ventilation, exhaled CO2 monitoring can provide valuable patient safety information and critical physiologic data in regard to the ventilation and perfusion matching in the lungs, cardiac output, and metabolic rate. Despite these important clinical monitoring benefits and widespread availability, exhaled CO2 monitoring is often underutilized. The purpose of this paper is to review the importance and present the extensive body of knowledge to support the use of exhaled CO2 monitoring in various areas of clinical practice. Advanced application concepts and the future development of exhaled CO2 monitoring will also be discussed.

  1. Measurement of transfer factor during constant exhalation.

    PubMed Central

    Wilson, A. F.; Hearne, J.; Brenner, M.; Alfonso, R.

    1994-01-01

    BACKGROUND--Transfer factor of the lung for carbon monoxide (TLCO) was measured by a new method based on analysis of the ratio of the concentrations of carbon monoxide to an inert gas (methane) relative to lung volume during a constant exhalation. Since this new technique is based solely upon exhalation, anomalies associated with inspiration and breath holding do not affect results. Additionally, because prolonged breath holding is not required, measurements can readily be made in dyspnoeic patients. METHODS--Exhalation TLCO (TLCO,ex) was compared with the standard (Jones and Meade) 10 second breath holding TLCO (TLCO,bh) in 100 consecutive patients. Patients did not practise the exhalation manoeuvre prior to testing. RESULTS--The comparative results were very close; mean difference (bias) +/- standard deviation (precision) was 0.05 (0.84) mmol/min/kPa. The relation was equally strong in patients with severe pulmonary disease; for patients with FEV1 < 1.51 the mean difference was 0.21 (0.80) mmol/min/kPa. CONCLUSIONS--Since the results were essentially identical between the techniques, it seems that comparable pathophysiological factors affect TLCO during breath holding and constant exhalation. Constant exhalation may therefore be a useful alternative to the breath holding technique for clinical measurement of TLCO. PMID:7831628

  2. Elevation in Exhaled Nitric Oxide Predicts for Radiation Pneumonitis

    SciTech Connect

    Guerrero, Thomas; Martinez, Josue; McCurdy, Matthew R.; Wolski, Michael; McAleer, Mary Francis

    2012-02-01

    Purpose: Radiation pneumonitis is a major toxicity after thoracic radiotherapy (RT), with no method available to accurately predict the individual risk. This was a prospective study to evaluate exhaled nitric oxide as a predictive biomarker for radiation pneumonitis in esophageal cancer patients. Patients and Methods: A total of 34 patients prescribed neoadjuvant chemoradiotherapy for esophageal cancer were enrolled in the present trial. Each patient underwent respiratory surveys and exhaled nitric oxide (NO) measurements before, at the end of, and 1 to 2 months after completing RT. Pneumonitis toxicity was scored using the Common Terminology Criteria for Adverse Events, version 4.0. The demographics, dosimetric factors, and exhaled NO levels were evaluated for correlation with symptomatic patients (scores {>=}2). Results: Of the 34 patients, 28 were evaluable. All had received 50.4 Gy RT with concurrent chemotherapy. The pneumonitis toxicity score was Grade 3 for 1, Grade 2 for 3, Grade 1 for 7, and Grade 0 for 17. The dosimetric factors were not predictive of symptoms. The mean exhaled NO level measured before, at completion, and at restaging was 17.3 {+-} 8.5 (range, 5.5-36.7), 16.0 {+-} 14.2 (range, 5.8-67.7), and 14.7 {+-} 6.2 (range, 5.5-28.0) parts per billion, respectively. The ratio of exhaled NO at the end of RT vs. before treatment was 3.4 (range, 1.7-6.7) for the symptomatic and 0.8 (range, 0.3-1.3) for the asymptomatic (p = .0017) patients. The elevation in exhaled NO preceded the peak symptoms by 33 days (range, 21-50). The interval to peak symptoms was inversely related to the exhaled NO elevation. Conclusions: Elevations in exhaled NO at the end of RT was found to predict for radiation pneumonitis symptoms.

  3. Health assessment of natural radioactivity and radon exhalation rate in granites used as building materials in Lebanon.

    PubMed

    Kobeissi, M A; El-Samad, O; Rachidi, I

    2013-03-01

    Measurements of specific activities (Bq kg(-1)) of gamma-emissions from radioactive nuclides, (238)U, (226)Ra, (214)Bi, (232)Th, (212)Pb and (40)K, contained in 28 granite types, used as building materials in indoors in Lebanon, were performed on the powdered granites. The concentration of the nuclides, (226)Ra, (232)Th and (40)K, in the granites varied from below detection level (BDL) to 494 Bq kg(-1), BDL to 157.2 Bq kg(-1) and BDL to 1776 Bq kg(-1), respectively. (226)Ra concentration equivalents, C(Raeq), were obtained and ranged between 37 and 591 Bq kg(-1), with certain values above the allowed limit of 370 Bq kg(-1). Calculated annual gamma-absorbed dose in air, D(aR), varied from 17.7 to 274.5 (nGy h(-1)). Annual effective dose, E (mSv y(-1)), of gamma radiations related to the studied granites and absorbed by the inhabitants was evaluated. E (mSv y(-1)) ranged from 0.09 to 1.35 mSv y(-1). Some granite types produced E above the allowed limit of 1 mSv y(-1) set by ICRP. Values of (222)Rn mass exhalation rate, E(M) (mBq kg(-1)h(-1))(,) in granite powder were obtained using the CR-39 detector technique. Diffusion factors, f, in 23 granite types were calculated with f ranging between (0.1 ± 0.02)×10(-2) and (6.6 ± 1.01)×10(-2).

  4. Analyzing spatial and temporal (222)Rn trends in Maine.

    PubMed

    Farah, Christopher; Beard, Kate; Hess, C T; Hock, Janet M

    2012-02-01

    Prolonged radon exposure has been linked to lung cancer. Cancer registry data indicates excess risk for age-adjusted lung cancer in Maine. Maine's mean residential radon activity exceeds the EPA maximum contaminant level (MCL). This paper describes the application of spatial autocorrelation methods to retrospective data as a means of analyzing radon activity in Maine. Retrospective air and well water radon activity data, sampled throughout Maine between 1993 and 2008, are standardized and geocoded for analysis. Three spatial autocorrelation algorithms-local Getis-Ord, local Moran, and spatial scan statistic-are used to identify spatial, temporal, and spatiotemporal radon activity clusters and/or outliers. Spatial clusters of high air- and well water-Rn activity are associated with Maine's Lucerne and Sebago granitic formations. Spatial clusters of low air- and well water-Rn activity are associated with Biddeford Granite and the metamorphic bedrock formation Silurian Ordovician Vassalboro. Space-time analysis indicates that most spatial clusters persist over the period of sampling. No significant temporal clusters are identified. Persistent spatial variations in radon may help to better understand and predict radon-related health risks associated with Maine residences.

  5. Study of gel materials as radioactive 222Rn gas detectors.

    PubMed

    Espinosa, G; Golzarri, J I; Rickards, J; Gammage, R B

    2006-01-01

    Commercial hair gel material (polyvinyl pyrolydone triethanolamine carbopol in water) and bacteriological agar (phycocolloid extracted from a group of red-purple algae, usually Gelidium sp.) have been studied as radioactive radon gas detectors. The detection method is based on the diffusion of the radioactive gas in the gel material, and the subsequent measurement of trapped products of the natural decay of radon by gamma spectrometry. From the several radon daughters with gamma radiation emission (214Pb, 214Bi, 214Po, 210Pb, 210Po), two elements, 214Pb (0.352 MeV) and 214Bi (0.609 MeV), were chosen for the analysis in this work; in order to determine the best sensitivity, corrections were made for the short half-life of the analysed isotopes. For the gamma spectrometry analysis, a hyperpure germanium solid state detector was used, associated with a PC multichannel analyser card with Maestro and Microsoft Excel software. The results show the viability of the method: a linear response in a wide radon concentration range (450-10,000 Bq m(-3)), reproducibility of data, easy handling and low cost of the gel material. This detection methodology opens new possibilities for measurements of radon and other radioactive gases.

  6. [Radon 222Rn in drinking water of Izera Plateau].

    PubMed

    Pachocki, Krzysztof A; Gorzkowski, Bohdan; Rózycki, Zdzisław; Wieprzowski, Kamil; Wilejczyk, Elzbieta; Smoter, Jacek

    2002-01-01

    Radon-222 concentration in surface water, wells water and tap water in the main towns and villages which are located in area of Izera Plateau has been quantitative determined. The measurements were performed using the alpha liquid scintillation counting method. The main waterworks in Szklarska Poreba is supplied with the surface water in which the radon concentration is low: from 1.23 Bq/l to 4.32 Bq/l. Waterworks "Huta Julia" is supplied with the ground water have a high radon concentration: from 294.4 Bq/l to 319.5 Bq/l. Majority of waterworks in Izera Plateau is supplied with the ground water in which the radon concentration is high: from 113.3 Bq/l to 464.5 Bq/l. The appropriate mean value for water of individual wells was 253.0 Bq/l, within the range from 25.8 Bq/l to 1095.1 Bq/l.

  7. EML pulse ionization chamber systems for /sup 222/Rn measurements

    SciTech Connect

    Fisenne, I M; Keller, H W

    1985-03-01

    Radon measurements have been performed with pulse ionization chambers at the Environmental Measurements Laboratory (EML) for over 35 years. This report describes the evolution of radon measurement systems, with emphasis on the continuous quality control efforts at EML. 38 refs., 3 figs., 3 tabs.

  8. Exhaled breath analysis and sleep.

    PubMed

    Carpagnano, Giovanna E

    2011-10-15

    It is currently estimated that the economic burden for obstructive sleep apnea syndrome (OSAS) cases not coming to medical attention is steadily increasing, thus making OSAS a major public health concern. For its increasing incidence among the common population, the interest of researchers and clinicians has been recently directed to the study of pathological mechanisms underlying sleep disorders. Current opinion is that airway inflammation and oxidative stress play a crucial role in the pathophysiology of OSAS. Recently there has been increasing interest in the investigation of lungs by non-invasive means measuring the exhaled breath volatile mediators, such as nitric oxide (NO), carbon monoxide (CO), ethane and pentane and finally the non-volatile substances in the liquid phase of exhalate, termed breath condensate. The non-invasiveness of these techniques for the study of airways affected by different respiratory disorders and among those, the OSAS, makes these ideally suited for the evaluation and serial monitoring of patients. Notwithstanding the increasing number of scientific contributions on the use of the exhaled markers in sleep disorders, at the moment, their use is not completely suitable for clinical application. An important contribution to the increase of our knowledge on exhaled markers and for their possible concrete application in clinical practice may come from future studies using proteomics, genomics and metabolomics. In this review, we focus on exhaled breath analysis giving an update on its general aspects, its application in OSAS, and finally its actual clinical applicability and areas for future direction.

  9. Inhaling to mitigate exhaled bioaerosols

    PubMed Central

    Edwards, David A.; Man, Jonathan C.; Brand, Peter; Katstra, Jeffrey P.; Sommerer, K.; Stone, Howard A.; Nardell, Edward; Scheuch, Gerhard

    2004-01-01

    Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These “exhaled bioaerosols” may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a simple means to potentially mitigate the spread of airborne infectious disease independently of the identity of the airborne pathogen or the nature of any specific therapy. We find that some normal human subjects expire many more bioaerosol particles than other individuals during quiet breathing and therefore bear the burden of production of exhaled bioaerosols. Administering nebulized isotonic saline to these “high-producer” individuals diminishes the number of exhaled bioaerosol particles expired by 72.10 ± 8.19% for up to 6 h. In vitro and in vivo experiments with saline and surfactants suggest that the mechanism of action of the nebulized saline relates to modification of the physical properties of the airway-lining fluid, notably surface tension. PMID:15583121

  10. Inhaling to mitigate exhaled bioaerosols.

    PubMed

    Edwards, David A; Man, Jonathan C; Brand, Peter; Katstra, Jeffrey P; Sommerer, K; Stone, Howard A; Nardell, Edward; Scheuch, Gerhard

    2004-12-14

    Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These "exhaled bioaerosols" may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a simple means to potentially mitigate the spread of airborne infectious disease independently of the identity of the airborne pathogen or the nature of any specific therapy. We find that some normal human subjects expire many more bioaerosol particles than other individuals during quiet breathing and therefore bear the burden of production of exhaled bioaerosols. Administering nebulized isotonic saline to these "high-producer" individuals diminishes the number of exhaled bioaerosol particles expired by 72.10 +/- 8.19% for up to 6 h. In vitro and in vivo experiments with saline and surfactants suggest that the mechanism of action of the nebulized saline relates to modification of the physical properties of the airway-lining fluid, notably surface tension.

  11. Exhaled Breath Analysis and Sleep

    PubMed Central

    Carpagnano, Giovanna E.

    2011-01-01

    It is currently estimated that the economic burden for obstructive sleep apnea syndrome (OSAS) cases not coming to medical attention is steadily increasing, thus making OSAS a major public health concern. For its increasing incidence among the common population, the interest of researchers and clinicians has been recently directed to the study of pathological mechanisms underlying sleep disorders. Current opinion is that airway inflammation and oxidative stress play a crucial role in the pathophysiology of OSAS. Recently there has been increasing interest in the investigation of lungs by non-invasive means measuring the exhaled breath volatile mediators, such as nitric oxide (NO), carbon monoxide (CO), ethane and pentane and finally the non-volatile substances in the liquid phase of exhalate, termed breath condensate. The non-invasiveness of these techniques for the study of airways affected by different respiratory disorders and among those, the OSAS, makes these ideally suited for the evaluation and serial monitoring of patients. Notwithstanding the increasing number of scientific contributions on the use of the exhaled markers in sleep disorders, at the moment, their use is not completely suitable for clinical application. An important contribution to the increase of our knowledge on exhaled markers and for their possible concrete application in clinical practice may come from future studies using proteomics, genomics and metabolomics. In this review, we focus on exhaled breath analysis giving an update on its general aspects, its application in OSAS, and finally its actual clinical applicability and areas for future direction. Citation: Carpagnano GE. Exhaled breath analysis and sleep. J Clin Sleep Med 2011;7(5):Supplement S34-S37. PMID:22003329

  12. Submarines, Spacecraft, and Exhaled Breath

    EPA Science Inventory

    The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled b...

  13. Submarines, Spacecraft, and Exhaled Breath

    EPA Science Inventory

    The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled b...

  14. Elective haemodialysis increases exhaled isoprene.

    PubMed

    Lirk, Philipp; Bodrogi, Florian; Raifer, Hartmann; Greiner, Karin; Ulmer, Hanno; Rieder, Josef

    2003-05-01

    Uraemic odour is a characteristic feature of patients with end-stage renal disease (ESRD). However, few investigations have been carried out into the composition of exhaled air in ESRD patients undergoing haemodialysis (HD). Increases of exhaled isoprene levels by a factor of up to 2.7 following HD have been reported. We attempted to confirm these findings in 50 patients undergoing HD using haemophan (n=23) or polysulphone (n=27) dialysis membranes. Parallel evaluation of ambient air, calorie intake, medication and haemodynamic variables was performed. Samples were analysed using proton transfer reaction-mass spectrometry (PTR-MS). Significant changes in breath isoprene concentration were observed when comparing patients before [39.14+/-14.96 parts per billion (ppbv)] and after (63.54+/-27.59 ppbv) dialysis (P<0.001). The quotient of values before and after dialysis was 1.84 (SD 1.41). No significant differences in isoprene kinetics were found between the use of haemophan and polysulphone membranes. No significant correlations were observed between isoprene quotients and variations in blood pressure during HD, calorie intake, ingestion of lipid-lowering drugs or serum lipid levels. Isoprene concentration was higher in the exhaled air of patients after HD as compared with values before HD. Large interindividual variability existed in isoprene kinetics. Oxidative stress appears to be an unlikely cause for this rise. An alternative hypothesis is an influence of respiratory variables on isoprene exhalation based upon Henry's law constant. We therefore propose to perform online monitoring of isoprene exhalation by PTR-MS during the HD session to investigate the possible influence of respiratory variables.

  15. Ratio

    NASA Astrophysics Data System (ADS)

    Webster, Nathan A. S.; Pownceby, Mark I.; Madsen, Ian C.; Studer, Andrew J.; Manuel, James R.; Kimpton, Justin A.

    2014-12-01

    Effects of basicity, B (CaO:SiO2 ratio) on the thermal range, concentration, and formation mechanisms of silico-ferrite of calcium and aluminum (SFCA) and SFCA-I iron ore sinter bonding phases have been investigated using an in situ synchrotron X-ray diffraction-based methodology with subsequent Rietveld refinement-based quantitative phase analysis. SFCA and SFCA-I phases are the key bonding materials in iron ore sinter, and improved understanding of the effects of processing parameters such as basicity on their formation and decomposition may assist in improving efficiency of industrial iron ore sintering operations. Increasing basicity significantly increased the thermal range of SFCA-I, from 1363 K to 1533 K (1090 °C to 1260 °C) for a mixture with B = 2.48, to ~1339 K to 1535 K (1066 °C to 1262 °C) for a mixture with B = 3.96, and to ~1323 K to 1593 K (1050 °C to 1320 °C) at B = 4.94. Increasing basicity also increased the amount of SFCA-I formed, from 18 wt pct for the mixture with B = 2.48 to 25 wt pct for the B = 4.94 mixture. Higher basicity of the starting sinter mixture will, therefore, increase the amount of SFCA-I, considered to be more desirable of the two phases. Basicity did not appear to significantly influence the formation mechanism of SFCA-I. It did, however, affect the formation mechanism of SFCA, with the decomposition of SFCA-I coinciding with the formation of a significant amount of additional SFCA in the B = 2.48 and 3.96 mixtures but only a minor amount in the highest basicity mixture. In situ neutron diffraction enabled characterization of the behavior of magnetite after melting of SFCA produced a magnetite plus melt phase assemblage.

  16. Comparison of select analytes in exhaled aerosol from e-cigarettes with exhaled smoke from a conventional cigarette and exhaled breaths.

    PubMed

    Long, Gerald A

    2014-10-27

    Exhaled aerosols were collected following the use of two leading U.S. commercial electronic cigarettes (e-cigarettes) and a conventional cigarette by human subjects and analyzed for phenolics, carbonyls, water, glycerin and nicotine using a vacuum-assisted filter pad capture system. Exhaled breath blanks were determined for each subject prior to each product use and aerosol collection session. Distribution and mass balance of exhaled e-cigarette aerosol composition was greater than 99.9% water and glycerin, and a small amount (<0.06%) of nicotine. Total phenolic content in exhaled e-cigarette aerosol was not distinguishable from exhaled breath blanks, while total phenolics in exhaled cigarette smoke were significantly greater than in exhaled e-cigarette aerosol and exhaled breaths, averaging 66 µg/session (range 36 to 117 µg/session). The total carbonyls in exhaled e-cigarette aerosols were also not distinguishable from exhaled breaths or room air blanks. Total carbonyls in exhaled cigarette smoke was significantly greater than in exhaled e-cigarette aerosols, exhaled breath and room air blanks, averaging 242 µg/session (range 136 to 352 µg/session). These results indicate that exhaled e-cigarette aerosol does not increase bystander exposure for phenolics and carbonyls above the levels observed in exhaled breaths of air.

  17. Comparison of Select Analytes in Exhaled Aerosol from E-Cigarettes with Exhaled Smoke from a Conventional Cigarette and Exhaled Breaths

    PubMed Central

    Long, Gerald A.

    2014-01-01

    Exhaled aerosols were collected following the use of two leading U.S. commercial electronic cigarettes (e-cigarettes) and a conventional cigarette by human subjects and analyzed for phenolics, carbonyls, water, glycerin and nicotine using a vacuum-assisted filter pad capture system. Exhaled breath blanks were determined for each subject prior to each product use and aerosol collection session. Distribution and mass balance of exhaled e-cigarette aerosol composition was greater than 99.9% water and glycerin, and a small amount (<0.06%) of nicotine. Total phenolic content in exhaled e-cigarette aerosol was not distinguishable from exhaled breath blanks, while total phenolics in exhaled cigarette smoke were significantly greater than in exhaled e-cigarette aerosol and exhaled breaths, averaging 66 µg/session (range 36 to 117 µg/session). The total carbonyls in exhaled e-cigarette aerosols were also not distinguishable from exhaled breaths or room air blanks. Total carbonyls in exhaled cigarette smoke was significantly greater than in exhaled e-cigarette aerosols, exhaled breath and room air blanks, averaging 242 µg/session (range 136 to 352 µg/session). These results indicate that exhaled e-cigarette aerosol does not increase bystander exposure for phenolics and carbonyls above the levels observed in exhaled breaths of air. PMID:25350011

  18. Exhaled methane concentration profiles during exercise on an ergometer

    PubMed Central

    Szabó, A; Ruzsanyi, V; Unterkofler, K; Mohácsi, Á; Tuboly, E; Boros, M; Szabó, G; Hinterhuber, H; Amann, A

    2016-01-01

    Exhaled methane concentration measurements are extensively used in medical investigation of certain gastrointestinal conditions. However, the dynamics of endogenous methane release is largely unknown. Breath methane profiles during ergometer tests were measured by means of a photoacoustic spectroscopy based sensor. Five methane-producing volunteers (with exhaled methane level being at least 1 ppm higher than room air) were measured. The experimental protocol consisted of 5 min rest—15 min pedalling (at a workload of 75 W)—5 min rest. In addition, hemodynamic and respiratory parameters were determined and compared to the estimated alveolar methane concentration. The alveolar breath methane level decreased considerably, by a factor of 3–4 within 1.5 min, while the estimated ventilation-perfusion ratio increased by a factor of 2–3. Mean pre-exercise and exercise methane concentrations were 11.4 ppm (SD:7.3) and 2.8 ppm (SD:1.9), respectively. The changes can be described by the high sensitivity of exhaled methane to ventilationperfusion ratio and are in line with the Farhi equation. PMID:25749807

  19. Detection of Δ9-tetrahydrocannabinol in exhaled breath collected from cannabis users.

    PubMed

    Beck, Olof; Sandqvist, Sören; Dubbelboer, Ilse; Franck, Johan

    2011-10-01

    Exhaled breath has recently been proposed as a new possible matrix for drugs of abuse testing. A key drug is cannabis, and the present study was aimed at investigating the possibility of detecting tetrahydrocannabinol and tetrahydrocannabinol carboxylic acid in exhaled breath after cannabis smoking. Exhaled breath was sampled from 10 regular cannabis users and 8 controls by directing the exhaled breath by suction through an Empore C(18) disk. The disk was extracted with hexane/ethyl acetate, and the resulting extract was evaporated to dryness and redissolved in 100 μL hexane/ethyl acetate. A 3-μL aliquot was injected onto the LC-MS-MS system and analyzed using positive electrospray ionization and selected reaction monitoring. In samples collected 1-12 h after cannabis smoking, tetrahydrocannabinol was detected in all 10 subjects. The rate of excretion was between 9.0 and 77.3 pg/min. Identification of tetrahydrocannabinol was based on correct retention time relative to tetrahydrocannabinol-d(3) and correct product ion ratio. In three samples, peaks were observed for tetrahydrocannabinol carboxylic acid, but these did not fulfill identification criteria. Neither tetrahydrocannabinol or tetrahydrocannabinol carboxylic acid was detected in the controls. These results confirm older reports that tetrahydrocannabinol is present in exhaled breath following cannabis smoking and extend the detection time from minutes to hours. The results further support the idea that exhaled breath is a promising matrix for drugs-of-abuse testing.

  20. Low Levels of Exhaled Surfactant Protein A Associated With BOS After Lung Transplantation

    PubMed Central

    Ericson, Petrea A.; Mirgorodskaya, Ekaterina; Hammar, Oscar S.; Viklund, Emilia A.; Almstrand, Ann-Charlotte R.; Larsson, Per J-W.; Riise, Gerdt C.; Olin, Anna-Carin

    2016-01-01

    Background There is no clinically available marker for early detection or monitoring of chronic rejection in the form of bronchiolitis obliterans syndrome (BOS), the main long-term complication after lung transplantation. Sampling and analysis of particles in exhaled air is a valid, noninvasive method for monitoring surfactant protein A (SP-A) and albumin in the distal airways. Methods We asked whether differences in composition of exhaled particles can be detected when comparing stable lung transplant recipients (LTRs) (n = 26) with LTRs who develop BOS (n = 7). A comparison between LTRs and a matching group of healthy controls (n = 33) was also conducted. Using a system developed in-house, particles were collected from exhaled air by the principal of inertial impaction before chemical analysis by immunoassays. Results Surfactant protein A in exhaled particles and the SP-A/albumin ratio were lower (P = 0.002 and P = 0.0001 respectively) in the BOS group compared to the BOS-free group. LTRs exhaled higher amount of particles (P < 0.0001) and had lower albumin content (P < 0.0001) than healthy controls. Conclusions We conclude that low levels of SP-A in exhaled particles are associated with increased risk of BOS in LTRs. The possibility that this noninvasive method can be used to predict BOS onset deserves further study with prospective and longitudinal approaches. PMID:27795995

  1. Determination of methadone in exhaled breath condensate by liquid chromatography-tandem mass spectrometry.

    PubMed

    Beck, Olof; Sandqvist, Sören; Eriksen, Paul; Franck, Johan; Palmskog, Göran

    2011-04-01

    Within the field of toxicology exhaled breath is used as specimen only for determination of alcohol. However, it was recently discovered that when using sensitive liquid chromatography-mass spectrometry (LC-MS) technique, amphetamine, methamphetamine, and methadone are detectable in exhaled breath following intake by drug addicts. We therefore undertook to develop a method for determination of methadone in exhaled breath condensate from patients undergoing methadonemaintenance treatment. Exhaled breath condensate was collected from 14 patients after intake of the daily methadone dose. The exhaled breath condensate was collected for 10 min using an Ecoscreen instrument. After extraction of any trapped methadone from the condensate by solid-phase extraction, the final extract was analyzed by a combined LC-MS-MS method. Recovery of methadone from breath condensate in the solid-phase extraction was 104%, no significant matrix effects were observed, and the quantification using methadone-d(3) as internal standard was accurate (10% bias) and precise (coefficient of variation 6.2%). Methadone was indisputably identified by means of the MS technique in exhaled breath condensate from all 14 patients. Identification was based on monitoring two product ions in selected reaction monitoring mode with correct relative ratio (± 20%) and correct retention time. Excretion rates ranged from 23.6 to 275 pg/min. No methadone was detected in five control subjects (< 2 pg/min). This finding confirms that methadone is present in exhaled breath from patients in methadone treatment. Collection of exhaled breath specimen is likely to be complementary to other matrices presently in use in testing for drugs-of-abuse.

  2. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  3. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  4. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  5. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation... continuous rate of 85 liters per minute. (b) The exhalation resistance of demand apparatus shall not...

  6. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation... continuous rate of 85 liters per minute. (b) The exhalation resistance of demand apparatus shall not...

  7. Medical diagnostics by laser-based analysis of exhaled breath

    NASA Astrophysics Data System (ADS)

    Giubileo, Gianfranco

    2002-08-01

    IMany trace gases can be found in the exhaled breath, some of them giving the possibility of a non invasive diagnosis of related diseases or allowing the monitoring of the disease in the course of its therapy. In the present lecture the principle of medical diagnosis based on the breath analysis will be introduced and the detection of trace gases in exhaled breath by high- resolution molecular spectroscopy in the IR spectral region will be discussed. A number of substrates and the optical systems for their laser detection will be reported. The following laser based experimental systems has been realised in the Molecular Spectroscopy Laboratory in ENEA in Frascati for the analysis of specific substances in the exhaled breath. A tuneable diode laser absorption spectroscopy (TDLAS) appartus for the measurement of 13C/12C isotopic ratio in carbon dioxide, a TDLAS apparatus for the detection of CH4 and a CO2 laser based photoacoustic system to detect trace ethylene at atmospheric pressure. The experimental set-up for each one of the a.m. optical systems will be shown and the related medical applications will be illustrated. The concluding remarks will be focuses on chemical species that are of major interest for medical people today and their diagnostic ability.

  8. Variations of the ambient dose equivalent rate in the ground level air.

    PubMed

    Lebedyte, M; Butkus, D; Morkŭnas, G

    2003-01-01

    The ambient dose equivalent rate is caused by ionizing radiation of radionuclides in the atmosphere and on the ground surface as well as by cosmic radiation. Seasonal and diurnal variations of the ambient dose equivalent rate (ADER) in the ground level air are influenced by the concentration of 222Rn daughters. The 222Rn concentration in the ground level atmosphere, in turn, depends on the rate of the 222Rn exhalation from soil and turbulent air mixing. Its diurnal and seasonal variations depend on meteorological conditions. The aim of this study is to estimate the influence of variations of the rate of the 222Rn exhalation from soil and its concentrations in the ground level air on variations of ADER in the ground level air, as well as the dependence of these parameters on meteorological conditions. The 222Rn diffusion coefficient and its exhalation rate in undisturbed loamy soil have been determined. The 222Rn concentration in the soil air and its concentration in the ground level air correlate inversely (correlation coefficient is r = -0.62). The main factors determining the 222Rn exhalation from soil are: the soil temperature (r = 0.64), the difference in temperature of soil and air (r = 0.57), and the precipitation amount (r = 0.50). The intensity of gamma radiation in the ground level air is mostly related to the 222Rn concentration in the air (r = 0.62), while the effect of the exhalation rate from soil is relatively low (r = 0.36). It has been shown that ADER due to 222Rn progeny causes only 7-16% of the total ADER and influences its variation. The comparison of variations of ADER due to 222Rn progeny and the total ADER during several years shows that these parameters correlate positively.

  9. Characterizing exhaled airflow from breathing and talking.

    PubMed

    Gupta, Jitendra K; Lin, Chao-Hsin; Chen, Qingyan

    2010-02-01

    The exhaled air of infected humans is one of the prime sources of contagious viruses. The exhaled air comes from respiratory events such as the coughing, sneezing, breathing and talking. Accurate information on the thermo-fluid characteristics of the exhaled airflow can be important for prediction of infectious disease transmission. The present study developed a source model to provide the thermo-fluid conditions of the exhaled air from the breathing and talking processes. The source model is a set of equations obtained from the measurements of the flow rate, flow direction, and area of mouth/nose opening with human subjects. It was found that the exhaled flow rate over time can be represented as a sinusoidal function for breathing and a constant for talking. The flow rates can be calculated by physiological parameters of a subject. The direction of the exhalation jet did not vary much between subjects and the area of mouth/nose opening could be regarded as a constant. Though the mouth/nose opening size varied among subjects, they were not correlated with the physiological parameters of the subjects. If combined with appropriate virus and droplet distribution information, the model can be used to describe the disease source due to breathing and talking. Accurate prediction of airborne disease transmission, and the infection prone zones, can aid in identifying and implementing the control strategies. With the recent advancements, Computational Fluid Dynamics (CFD) has become a powerful tool in predicting the disease transmission. Accurate prediction of the transmission by these CFD simulations requires information on sources and sinks of infectious viruses and models for dispersion of these viruses. The exhaled air of an infected human is one of the prime sources of disease viruses. In the present study, measurements of the flow were conducted on human subjects to develop models for the flow boundary conditions for the exhalation and inhalation during breathing and

  10. Submarines, spacecraft and exhaled breath.

    PubMed

    Pleil, Joachim D; Hansel, Armin

    2012-03-01

    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  11. Exhaled breath analysis for lung cancer.

    PubMed

    Dent, Annette G; Sutedja, Tom G; Zimmerman, Paul V

    2013-10-01

    Early diagnosis of lung cancer results in improved survival compared to diagnosis with more advanced disease. Early disease is not reliably indicated by symptoms. Because investigations such as bronchoscopy and needle biopsy have associated risks and substantial costs, they are not suitable for population screening. Hence new easily applicable tests, which can be used to screen individuals at risk, are required. Biomarker testing in exhaled breath samples is a simple, relatively inexpensive, non-invasive approach. Exhaled breath contains volatile and non-volatile organic compounds produced as end-products of metabolic processes and the composition of such compounds varies between healthy subjects and subjects with lung cancer. Many studies have analysed the patterns of these compounds in exhaled breath. In addition studies have also reported that the exhaled breath condensate (EBC) can reveal gene mutations or DNA abnormalities in patients with lung cancer. This review has summarised the scientific evidence demonstrating that lung cancer has distinct chemical profiles in exhaled breath and characteristic genetic changes in EBC. It is not yet possible to accurately identify individuals with lung cancer in at risk populations by any of these techniques. However, analysis of both volatile organic compounds in exhaled breath and of EBC have great potential to become clinically useful diagnostic and screening tools for early stage lung cancer detection.

  12. Exhaled breath analysis for lung cancer

    PubMed Central

    Sutedja, Tom G.; Zimmerman, Paul V.

    2013-01-01

    Early diagnosis of lung cancer results in improved survival compared to diagnosis with more advanced disease. Early disease is not reliably indicated by symptoms. Because investigations such as bronchoscopy and needle biopsy have associated risks and substantial costs, they are not suitable for population screening. Hence new easily applicable tests, which can be used to screen individuals at risk, are required. Biomarker testing in exhaled breath samples is a simple, relatively inexpensive, non-invasive approach. Exhaled breath contains volatile and non-volatile organic compounds produced as end-products of metabolic processes and the composition of such compounds varies between healthy subjects and subjects with lung cancer. Many studies have analysed the patterns of these compounds in exhaled breath. In addition studies have also reported that the exhaled breath condensate (EBC) can reveal gene mutations or DNA abnormalities in patients with lung cancer. This review has summarised the scientific evidence demonstrating that lung cancer has distinct chemical profiles in exhaled breath and characteristic genetic changes in EBC. It is not yet possible to accurately identify individuals with lung cancer in at risk populations by any of these techniques. However, analysis of both volatile organic compounds in exhaled breath and of EBC have great potential to become clinically useful diagnostic and screening tools for early stage lung cancer detection. PMID:24163746

  13. Radon and Thoron exhalation rate map in Japan

    SciTech Connect

    Masahiro, Hosoda; Michikuni, Shimo; Kazuyuki, Minami; Kazutaka, Ejiri; Masato, Sugino; Masahide, Furukawa; Masahiro, Fukushi

    2008-08-07

    Measurements of radon and thoron exhalation rates have been done using the radon and thoron exhalation rate measuring instrument adopting the accumulation method. We obtained the 111 data in the 40 sites of the 14 prefectures in Japan. The arithmetic average value of the radon and thoron exhalation rates by all 111 data were obtained to be 8.6 mBq{center_dot}m{sup -2}{center_dot}s{sup -1} and 0.80 Bq{center_dot}m{sup -2}{center_dot}s{sup -1}, respectively, and we have reported the radon and thoron exhalation rates in relation to the geological features. The relation between the exhalation rate and geology was shown that the exhalation rate had an increasing tendency in order of basic rock, neutral rock and acidic rock. We made the nationwide exhalation-rate map using the survey data of exhalation-rate of radon and thoron and the geological distribution map.

  14. The origin of mouth-exhaled ammonia.

    PubMed

    Chen, W; Metsälä, M; Vaittinen, O; Halonen, L

    2014-09-01

    It is known that the oral cavity is a production site for mouth-exhaled NH3. However, the mechanism of NH3 production in the oral cavity has been unclear. Since bacterial urease in the oral cavity has been found to produce ammonia from oral fluid urea, we hypothesize that oral fluid urea is the origin of mouth-exhaled NH3. Our results show that under certain conditions a strong correlation exists between oral fluid urea and oral fluid ammonia (NH4(+)+NH3) (rs = 0.77, p < 0.001). We also observe a strong correlation between oral fluid NH3 and mouth-exhaled NH3 (rs = 0.81, p < 0.001). We conclude that three main factors affect the mouth-exhaled NH3 concentration: urea concentration, urease activity and oral fluid pH. Bacterial urease catalyses the hydrolysis of oral fluid urea to ammonia (NH4(+)+NH3). Oral fluid ammonia (NH4(+)+NH3) and pH determine the concentration of oral fluid NH3, which evaporates from oral fluid into gas phase and turns to mouth-exhaled NH3.

  15. Screening for emphysema via exhaled volatile organic compounds.

    PubMed

    Cristescu, S M; Gietema, H A; Blanchet, L; Kruitwagen, C L J J; Munnik, P; van Klaveren, R J; Lammers, J W J; Buydens, L; Harren, F J M; Zanen, P

    2011-12-01

    Chronic obstructive pulmonary disease (COPD)/emphysema risk groups are well defined and screening allows for early identification of disease. The capability of exhaled volatile organic compounds (VOCs) to detect emphysema, as found by computed tomography (CT) in current and former heavy smokers participating in a lung cancer screening trial, was investigated. CT scans, pulmonary function tests and breath sample collections were obtained from 204 subjects. Breath samples were analyzed with a proton-transfer reaction mass spectrometer (PTR-MS) to obtain VOC profiles listed as ions at various mass-to-charge ratios (m/z). Using bootstrapped stepwise forward logistic regression, we identified specific breath profiles as a potential tool for the diagnosis of emphysema, of airflow limitation or gas-exchange impairment. A marker for emphysema was found at m/z 87 (tentatively attributed to 2-methylbutanal). The area under the receiver operating characteristic curve (ROC) of this marker to diagnose emphysema was 0.588 (95% CI 0.453-0.662). Mass-to-charge ratios m/z 52 (most likely chloramine) and m/z 135 (alkyl benzene) were linked to obstructive disease and m/z 122 (most probably alkyl homologs) to an impaired diffusion capacity. ROC areas were 0.646 (95% CI 0.562-0.730) and 0.671 (95% CI 0.524-0.710), respectively. In the screening setting, exhaled VOCs measured by PTR-MS constitute weak markers for emphysema, pulmonary obstruction and impaired diffusion capacity.

  16. Combined sensing platform for advanced diagnostics in exhaled mouse breath

    NASA Astrophysics Data System (ADS)

    Fortes, Paula R.; Wilk, Andreas; Seichter, Felicia; Cajlakovic, Merima; Koestler, Stefan; Ribitsch, Volker; Wachter, Ulrich; Vogt, Josef; Radermacher, Peter; Carter, Chance; Raimundo, Ivo M.; Mizaikoff, Boris

    2013-03-01

    Breath analysis is an attractive non-invasive strategy for early disease recognition or diagnosis, and for therapeutic progression monitoring, as quantitative compositional analysis of breath can be related to biomarker panels provided by a specific physiological condition invoked by e.g., pulmonary diseases, lung cancer, breast cancer, and others. As exhaled breath contains comprehensive information on e.g., the metabolic state, and since in particular volatile organic constituents (VOCs) in exhaled breath may be indicative of certain disease states, analytical techniques for advanced breath diagnostics should be capable of sufficient molecular discrimination and quantification of constituents at ppm-ppb - or even lower - concentration levels. While individual analytical techniques such as e.g., mid-infrared spectroscopy may provide access to a range of relevant molecules, some IR-inactive constituents require the combination of IR sensing schemes with orthogonal analytical tools for extended molecular coverage. Combining mid-infrared hollow waveguides (HWGs) with luminescence sensors (LS) appears particularly attractive, as these complementary analytical techniques allow to simultaneously analyze total CO2 (via luminescence), the 12CO2/13CO2 tracer-to-tracee (TTR) ratio (via IR), selected VOCs (via IR) and O2 (via luminescence) in exhaled breath, yet, establishing a single diagnostic platform as both sensors simultaneously interact with the same breath sample volume. In the present study, we take advantage of a particularly compact (shoebox-size) FTIR spectrometer combined with novel substrate-integrated hollow waveguide (iHWG) recently developed by our research team, and miniaturized fiberoptic luminescence sensors for establishing a multi-constituent breath analysis tool that is ideally compatible with mouse intensive care stations (MICU). Given the low tidal volume and flow of exhaled mouse breath, the TTR is usually determined after sample collection via gas

  17. Nasal contribution to exhaled nitric oxide during exhalation against resistance or during breath holding

    PubMed Central

    Kharitonov, S. A.; Barnes, P. J.

    1997-01-01

    BACKGROUND: The concentration of nitric oxide (NO) is increased in the exhaled air of patients with inflammation of the airways, suggesting that this may be a useful measurement to monitor inflammation in diseases such as asthma. However, there have been concerns that exhaled NO may be contaminated by the high concentrations of NO derived from the upper airways, and that this may account for differences in reported values of exhaled NO using different techniques. A study was performed, with argon as a tracer, to determine the extent of nasal contamination of exhaled NO using different expiratory manoeuvres. METHODS: Exhaled and nasal NO were measured by a chemiluminescence analyser. Argon (4.8%) was delivered continuously to the nose. Gas was sampled from the posterior oropharynx and argon and carbon dioxide were measured by mass spectrometry at the same time as NO. RESULTS: During a single expiration against a low resistance and during breath holding there was no evidence for nasal contamination, whereas during exhalation without resistance argon concentration in the oropharynx was increased from 0.91% (95% CI 0.84% to 0.98%) in ambient air to 1.28% (0.9% to 2.24%, p < 0.0001) during a single breath or 2.37% (2.29% to 2.51%, p < 0.0001) during tidal breathing. CONCLUSIONS: Collection of exhaled NO in a reservoir during tidal breathing is likely to be contaminated by NO derived from the nose and this may underestimate any increases in NO derived from the lower respiratory tract in inflammatory diseases. However, with slow expiration against a resistance and created back pressure to close the soft palate, there is no contamination of exhaled air which then reflects concentrations of NO in the lower airways. 


 PMID:9227721

  18. Nasal contribution to exhaled nitric oxide during exhalation against resistance or during breath holding.

    PubMed

    Kharitonov, S A; Barnes, P J

    1997-06-01

    The concentration of nitric oxide (NO) is increased in the exhaled air of patients with inflammation of the airways, suggesting that this may be a useful measurement to monitor inflammation in diseases such as asthma. However, there have been concerns that exhaled NO may be contaminated by the high concentrations of NO derived from the upper airways, and that this may account for differences in reported values of exhaled NO using different techniques. A study was performed, with argon as a tracer, to determine the extent of nasal contamination of exhaled NO using different expiratory manoeuvres. Exhaled and nasal NO were measured by a chemiluminescence analyser. Argon (4.8%) was delivered continuously to the nose. Gas was sampled from the posterior oropharynx and argon and carbon dioxide were measured by mass spectrometry at the same time as NO. During a single expiration against a low resistance and during breath holding there was no evidence for nasal contamination, whereas during exhalation without resistance argon concentration in the oropharynx was increased from 0.91% (95% CI 0.84% to 0.98%) in ambient air to 1.28% (0.9% to 2.24%, p < 0.0001) during a single breath or 2.37% (2.29% to 2.51%, p < 0.0001) during tidal breathing. Collection of exhaled NO in a reservoir during tidal breathing is likely to be contaminated by NO derived from the nose and this may underestimate any increases in NO derived from the lower respiratory tract in inflammatory diseases. However, with slow expiration against a resistance and created back pressure to close the soft palate, there is no contamination of exhaled air which then reflects concentrations of NO in the lower airways.

  19. Novel method of measurement of radon exhalation from building materials.

    PubMed

    Awhida, A; Ujić, P; Vukanac, I; Đurašević, M; Kandić, A; Čeliković, I; Lončar, B; Kolarž, P

    2016-11-01

    In the era of the energy saving policy (i.e. more air tight doors and windows), the radon exhaled from building materials tends to increase its concentration in indoor air, which increases the importance of the measurement of radon exhalation from building materials. This manuscript presents a novel method of the radon exhalation measurement using only a HPGe detector or any other gamma spectrometer. Comparing it with the already used methods of radon exhalation measurements, this method provides the measurement of the emanation coefficient, the radon diffusion length and the radon exhalation rate, all within the same measurement, which additionally defines material's radon protective properties. Furthermore it does not necessitate additional equipment for radon or radon exhalation measurement, which simplifies measurement technique, and thus potentially facilitates introduction of legal obligation for radon exhalation determination in building materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Evaluation of the effect of a cover layer on radon exhalation from uranium mill tailings: transient radon flux analysis.

    PubMed

    Ferry, Cécile; Richon, Patrick; Beneito, Alain; Robé, Marie-Christine

    2002-01-01

    An experimental study concerning the transport of 222Rn in uranium mill tailings (UMTs) and in the cover layer was launched in 1997 with the participation of the French uranium mining company (COGEMA). Evaluation of the cover layer's effectiveness in reducing 222Rn flux emanating from UMTs was one of its objectives. In the first phase, the 222Rn flux densities were measured regularly on a UMT layer. In the second phase, the UMT was covered with a one-meter layer of compacted material consisting of crushed waste rock derived from mining activities. Radon-222 flux was then measured at the surface of this cover layer. Observations were compared with radon flux calculated using TRACI, a model for vertical water and gas flow and radon transport. The results show that the calculations bear a fair resemblance to the observations in both cases. They also show that the effectiveness of the cover layer calculated with TRACI, using the thickness and textural properties of the cover material, is very close to the measured effectiveness.

  1. EXHALED BREATH ANALYSIS FOR HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that...

  2. Drinking influences exhaled breath condensate acidity.

    PubMed

    Kullmann, Tamás; Barta, Imre; Antus, Balázs; Horváth, Ildikó

    2008-01-01

    Exhaled breath condensate analysis is a developing method for investigating airway pathology. Impact of food and drink on breath condensate composition has not been systematically addressed. The aim of the study was to follow exhaled breath condensate pH after drinking an acidic and a neutral beverage. Breath condensate, capillary blood, and urine of 12 healthy volunteers were collected before and after drinking either 1 l of coke or 1 l of mineral water. The pH of each sample was determined with a blood gas analyzer. The mean difference between the pH of two breath condensate samples collected within 15 min before drinking was 0.13+/-0.03. Condensate pH decreased significantly from 6.29+/-0.02 to 6.24+/-0.02 (p<0.03) after drinking coke and from 6.37+/-0.03 to 6.22+/-0.04 (p<0.003) after drinking water. Drinking coke induced significant changes in blood and urine pH as well. Drinking influences exhaled breath condensate composition and may contribute to the variability of exhaled breath condensate pH.

  3. EXHALED BREATH ANALYSIS FOR HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that...

  4. Chemiresistive Electronic Nose toward Detection of Biomarkers in Exhaled Breath.

    PubMed

    Moon, Hi Gyu; Jung, Youngmo; Han, Soo Deok; Shim, Young-Seok; Shin, Beomju; Lee, Taikjin; Kim, Jin-Sang; Lee, Seok; Jun, Seong Chan; Park, Hyung-Ho; Kim, Chulki; Kang, Chong-Yun

    2016-08-17

    Detection of gas-phase chemicals finds a wide variety of applications, including food and beverages, fragrances, environmental monitoring, chemical and biochemical processing, medical diagnostics, and transportation. One approach for these tasks is to use arrays of highly sensitive and selective sensors as an electronic nose. Here, we present a high performance chemiresistive electronic nose (CEN) based on an array of metal oxide thin films, metal-catalyzed thin films, and nanostructured thin films. The gas sensing properties of the CEN show enhanced sensitive detection of H2S, NH3, and NO in an 80% relative humidity (RH) atmosphere similar to the composition of exhaled breath. The detection limits of the sensor elements we fabricated are in the following ranges: 534 ppt to 2.87 ppb for H2S, 4.45 to 42.29 ppb for NH3, and 206 ppt to 2.06 ppb for NO. The enhanced sensitivity is attributed to the spillover effect by Au nanoparticles and the high porosity of villi-like nanostructures, providing a large surface-to-volume ratio. The remarkable selectivity based on the collection of sensor responses manifests itself in the principal component analysis (PCA). The excellent sensing performance indicates that the CEN can detect the biomarkers of H2S, NH3, and NO in exhaled breath and even distinguish them clearly in the PCA. Our results show high potential of the CEN as an inexpensive and noninvasive diagnostic tool for halitosis, kidney disorder, and asthma.

  5. Role of exhaled nitric oxide in asthma.

    PubMed

    Yates, D H

    2001-04-01

    Nitric oxide (NO), an evanescent atmospheric gas, has recently been discovered to be an important biological mediator in animals and humans. Nitric oxide plays a key role within the lung in the modulation of a wide variety of functions including pulmonary vascular tone, nonadrenergic non-cholinergic (NANC) transmission and modification of the inflammatory response. Asthma is characterized by chronic airway inflammation and increased synthesis of NO and other highly reactive and toxic substances (reactive oxygen species). Pro- inflammatory cytokines such as TNFalpha and IL-1beta are secreted in asthma and result in inflammatory cell recruitment, but also induce calcium- and calmodulin-independent nitric oxide synthases (iNOS) and perpetuate the inflammatory response within the airways. Nitric oxide is released by several pulmonary cells including epithelial cells, eosinophils and macrophages, and NO has been shown to be increased in conditions associated with airway inflammation, such as asthma and viral infections. Nitric oxide can be measured in the expired air of several species, and exhaled NO can now be rapidly and easily measured by the use of chemiluminescence analysers in humans. Exhaled NO is increased in steroid-naive asthmatic subjects and during an asthma exacerbation, although it returns to baseline levels with appropriate anti-inflammatory treatment, and such measurements have been proposed as a simple non-invasive method of measuring airway inflammation in asthma. Here the chemical and biological properties of NO are briefly discussed, followed by a summary of the methodological considerations relevant to the measurement of exhaled NO and its role in lung diseases including asthma. The origin of exhaled NO is considered, and brief mention made of other potential markers of airway inflammation or oxidant stress in exhaled breath.

  6. Analysis of Exhaled Breath for Disease Detection

    NASA Astrophysics Data System (ADS)

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-06-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  7. Analysis of exhaled breath for disease detection.

    PubMed

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-01-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  8. Geographical variation in the exhaled volatile organic compounds.

    PubMed

    Amal, Haitham; Leja, Marcis; Broza, Yoav Y; Tisch, Ulrike; Funka, Konrads; Liepniece-Karele, Inta; Skapars, Roberts; Xu, Zhen-Qin; Liu, Hu; Haick, Hossam

    2013-12-01

    Breath-gas analysis has demonstrated that concentration profiles of volatile organic compounds (VOCs) could be used for detecting a variety of diseases, among them gastric cancer (GC) and peptic ulcer disease (PUD). Here, we explore how geographical variation affects the disease-specific changes in the chemical composition of breath samples, as compared to control states (less severe gastric conditions). Alveolar exhaled breath samples from 260 patients were collected at two remotely different geographic locations (China and Latvia), following similar breath-collection protocols. Each cohort included 130 patients that were matched in terms of diagnosis (37 GC/32 PUD/61 controls), average age, gender ratio and smoking habits. Helicobacter Pylori infection, which is a major cause for GC and PUD, was found in part of the patients, as well as in part of the controls, at both locations. The breath samples were analyzed by gas chromatography/mass spectrometry, using the same equipment and protocol-of-experiment. We observed similar characteristic differences in the chemical composition of the breath samples between the study groups at the two locations, even though the exact composition of the breath samples differed. Both in China and Latvia, the GC patients and controls could be distinguished by differences in the average levels of 6-methyl-5-hepten-2-one; PUD patients were distinguished from controls by the levels of aromatic compounds and alcohols; GC and PUD patients could not be distinguished at either site. This pilot study indicates the limitations of chemical breath-gas analysis alone for identifying gastric diseases based on the concentration profiles of separate VOCs in international patient cohorts. We assume that these limitations would apply to other diseases as well. The presented data could potentially be useful for developing an alternative, universally applicable diagnostic method that relies on the detection of changes in the collective patterns of

  9. Methodological Issues of Sample Collection and Analysis of Exhaled Breath

    EPA Science Inventory

    Recommended standardized procedures have been developed for measurement of exhaled lower respiratory nitric oxide (NO) and nasal NO. It would be desirable to develop similar guidelines for the sampling of exhaled breath related to other compounds. For such systemic volatile o...

  10. Influenza virus in human exhaled breath: an observational study.

    PubMed

    Fabian, Patricia; McDevitt, James J; DeHaan, Wesley H; Fung, Rita O P; Cowling, Benjamin J; Chan, Kwok Hung; Leung, Gabriel M; Milton, Donald K

    2008-07-16

    Recent studies suggest that humans exhale fine particles during tidal breathing but little is known of their composition, particularly during infection. We conducted a study of influenza infected patients to characterize influenza virus and particle concentrations in their exhaled breath. Patients presenting with influenza-like-illness, confirmed influenza A or B virus by rapid test, and onset within 3 days were recruited at three clinics in Hong Kong, China. We collected exhaled breath from each subject onto Teflon filters and measured exhaled particle concentrations using an optical particle counter. Filters were analyzed for influenza A and B viruses by quantitative polymerase chain reaction (qPCR). Twelve out of thirteen rapid test positive patients provided exhaled breath filter samples (7 subjects infected with influenza B virus and 5 subjects infected with influenza A virus). We detected influenza virus RNA in the exhaled breath of 4 (33%) subjects--three (60%) of the five patients infected with influenza A virus and one (14%) of the seven infected with influenza B virus. Exhaled influenza virus RNA generation rates ranged from <3.2 to 20 influenza virus RNA particles per minute. Over 87% of particles exhaled were under 1 microm in diameter. These findings regarding influenza virus RNA suggest that influenza virus may be contained in fine particles generated during tidal breathing, and add to the body of literature suggesting that fine particle aerosols may play a role in influenza transmission.

  11. Methodological Issues of Sample Collection and Analysis of Exhaled Breath

    EPA Science Inventory

    Recommended standardized procedures have been developed for measurement of exhaled lower respiratory nitric oxide (NO) and nasal NO. It would be desirable to develop similar guidelines for the sampling of exhaled breath related to other compounds. For such systemic volatile o...

  12. Exhaled breath condensate pH assays.

    PubMed

    Davis, Michael D; Hunt, John

    2012-08-01

    Airway pH is central to the physiologic function and cellular biology of the airway. The causes of airway acidification include (1) hypopharyngeal gastric acid reflux with or without aspiration through the vocal cords, (2) inhalation of acid fog or gas (such as chlorine), and (3) intrinsic airway acidification caused by altered airway pH homeostasis in infectious and inflammatory disease processes. The recognition that relevant airway pH deviations occur in lung diseases is opening doors to new simple and inexpensive therapies. This recognition has resulted partly from the ability to use exhaled breath condensate as a window on airway acid-base balance.

  13. Influence of air pollution on exhaled carbon monoxide levels in smokers and non-smokers. A prospective cross-sectional study.

    PubMed

    Maga, Mikołaj; Janik, Maciej K; Wachsmann, Agnieszka; Chrząstek-Janik, Olga; Koziej, Mateusz; Bajkowski, Mateusz; Maga, Paweł; Tyrak, Katarzyna; Wójcik, Krzysztof; Gregorczyk-Maga, Iwona; Niżankowski, Rafał

    2017-01-01

    The poor air quality and cigarette smoking are the most important reasons for increased carbon monoxide (CO) level in exhaled air. However, the influence of high air pollution concentration in big cities on the exhaled CO level has not been well studied yet. To evaluate the impact of smoking habit and air pollution in the place of living on the level of CO in exhaled air. Citizens from two large cities and one small town in Poland were asked to complete a survey disclosing their place of residence, education level, work status and smoking habits. Subsequently, the CO level in their exhaled air was measured. Air quality data, obtained from the Regional Inspectorates of Environmental Protection, revealed the differences in atmospheric CO concentration between locations. 1226 subjects were divided into 4 groups based on their declared smoking status and place of living. The average CO level in exhaled air was significantly higher in smokers than in non-smokers (p<0.0001) as well as in non-smokers from big cities than non-smokers from small ones (p<0.0001). Created model showed that non-smokers from big cities have odds ratio of 125.3 for exceeding CO cutoff level of 4ppm compared to non-smokers from small towns. The average CO level in exhaled air is significantly higher in smokers than non-smokers. Among non-smokers, the average exhaled CO level is significantly higher in big city than small town citizens. These results suggest that permanent exposure to an increased concentration of air pollution and cigarette smoking affect the level of exhaled CO. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Quantifying Aerosol Delivery in Simulated Spontaneously Breathing Patients With Tracheostomy Using Different Humidification Systems With or Without Exhaled Humidity.

    PubMed

    Ari, Arzu; Harwood, Robert; Sheard, Meryl; Alquaimi, Maher Mubarak; Alhamad, Bshayer; Fink, James B

    2016-05-01

    Aerosol and humidification therapy are used in long-term airway management of critically ill patients with a tracheostomy. The purpose of this study was to determine delivery efficiency of jet and mesh nebulizers combined with different humidification systems in a model of a spontaneously breathing tracheotomized adult with or without exhaled heated humidity. An in vitro model was constructed to simulate a spontaneously breathing adult (tidal volume, 400 mL; breathing frequency, 20 breaths/min; inspiratory-expiratory ratio, 1:2) with a tracheostomy using a teaching manikin attached to a test lung through a collecting filter (Vital Signs Respirgard II). Exhaled heat and humidity were simulated using a cascade humidifier set to deliver 37°C and >95% relative humidity. Albuterol sulfate (2.5 mg/3 mL) was administered with a jet nebulizer (AirLife Misty Max) operated at 10 L/min and a mesh nebulizer (Aeroneb Solo) using a heated pass-over humidifier, unheated large volume humidifier both at 40 L/min output and heat-and-moisture exchanger. Inhaled drug eluted from the filter was analyzed via spectrophotometry (276 nm). Delivery efficiency of the jet nebulizer was less than that of the mesh nebulizer under all conditions (P < .05). Aerosol delivery with each nebulizer was greatest on room air and lowest when heated humidifiers with higher flows were used. Exhaled humidity decreased drug delivery up to 44%. The jet nebulizer was less efficient than the mesh nebulizer in all conditions tested in this study. Aerosol deposition with each nebulizer was lowest with the heated humidifier with high flow. Exhaled humidity reduced inhaled dose of drug compared with a standard model with nonheated/nonhumidified exhalation. Further clinical research is warranted to understand the impact of exhaled humidity on aerosol drug delivery in spontaneously breathing patients with tracheostomy using different types of humidifiers. Copyright © 2016 by Daedalus Enterprises.

  15. Fast and accurate exhaled breath ammonia measurement.

    PubMed

    Solga, Steven F; Mudalel, Matthew L; Spacek, Lisa A; Risby, Terence H

    2014-06-11

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

  16. Fast and Accurate Exhaled Breath Ammonia Measurement

    PubMed Central

    Solga, Steven F.; Mudalel, Matthew L.; Spacek, Lisa A.; Risby, Terence H.

    2014-01-01

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations. PMID:24962141

  17. Exhaled Breath Condensate: Technical and Diagnostic Aspects

    PubMed Central

    Konstantinidi, Efstathia M.; Lappas, Andreas S.; Tzortzi, Anna S.; Behrakis, Panagiotis K.

    2015-01-01

    Purpose. The aim of this study was to evaluate the 30-year progress of research on exhaled breath condensate in a disease-based approach. Methods. We searched PubMed/Medline, ScienceDirect, and Google Scholar using the following keywords: exhaled breath condensate (EBC), biomarkers, pH, asthma, gastroesophageal reflux (GERD), smoking, COPD, lung cancer, NSCLC, mechanical ventilation, cystic fibrosis, pulmonary arterial hypertension (PAH), idiopathic pulmonary fibrosis, interstitial lung diseases, obstructive sleep apnea (OSA), and drugs. Results. We found 12600 related articles in total in Google Scholar, 1807 in ScienceDirect, and 1081 in PubMed/Medline, published from 1980 to October 2014. 228 original investigation and review articles were eligible. Conclusions. There is rapidly increasing number of innovative articles, covering all the areas of modern respiratory medicine and expanding EBC potential clinical applications to other fields of internal medicine. However, the majority of published papers represent the results of small-scale studies and thus current knowledge must be further evaluated in large cohorts. In regard to the potential clinical use of EBC-analysis, several limitations must be pointed out, including poor reproducibility of biomarkers and absence of large surveys towards determination of reference-normal values. In conclusion, contemporary EBC-analysis is an intriguing achievement, but still in early stage when it comes to its application in clinical practice. PMID:26106641

  18. Exhaled Breath Condensate: Technical and Diagnostic Aspects.

    PubMed

    Konstantinidi, Efstathia M; Lappas, Andreas S; Tzortzi, Anna S; Behrakis, Panagiotis K

    2015-01-01

    The aim of this study was to evaluate the 30-year progress of research on exhaled breath condensate in a disease-based approach. We searched PubMed/Medline, ScienceDirect, and Google Scholar using the following keywords: exhaled breath condensate (EBC), biomarkers, pH, asthma, gastroesophageal reflux (GERD), smoking, COPD, lung cancer, NSCLC, mechanical ventilation, cystic fibrosis, pulmonary arterial hypertension (PAH), idiopathic pulmonary fibrosis, interstitial lung diseases, obstructive sleep apnea (OSA), and drugs. We found 12600 related articles in total in Google Scholar, 1807 in ScienceDirect, and 1081 in PubMed/Medline, published from 1980 to October 2014. 228 original investigation and review articles were eligible. There is rapidly increasing number of innovative articles, covering all the areas of modern respiratory medicine and expanding EBC potential clinical applications to other fields of internal medicine. However, the majority of published papers represent the results of small-scale studies and thus current knowledge must be further evaluated in large cohorts. In regard to the potential clinical use of EBC-analysis, several limitations must be pointed out, including poor reproducibility of biomarkers and absence of large surveys towards determination of reference-normal values. In conclusion, contemporary EBC-analysis is an intriguing achievement, but still in early stage when it comes to its application in clinical practice.

  19. Determining the radon exhalation rate from a gold mine tailings dump by measuring the gamma radiation.

    PubMed

    Ongori, Joash N; Lindsay, Robert; Newman, Richard T; Maleka, Peane P

    2015-02-01

    The mining activities taking place in Gauteng province, South Africa have caused millions of tons of rocks to be taken from underground to be milled and processed to extract gold. The uranium bearing tailings are placed in an estimated 250 dumps covering a total area of about 7000 ha. These tailings dumps contain considerable amounts of radium and have therefore been identified as large sources of radon. The size of these dumps make traditional radon exhalation measurements time consuming and it is difficult to get representative measurements for the whole dump. In this work radon exhalation measurements from the non-operational Kloof mine dump have been performed by measuring the gamma radiation from the dump fairly accurately over an area of more than 1 km(2). Radon exhalation from the mine dump have been inferred from this by laboratory-based and in-situ gamma measurements. Thirty four soil samples were collected at depths of 30 cm and 50 cm. The weighted average activity concentrations in the soil samples were 308 ± 7 Bq kg(-1), 255 ± 5 Bq kg(-1) and 18 ± 1 Bq kg(-1) for (238)U, (40)K and (232)Th, respectively. The MEDUSA (Multi-Element Detector for Underwater Sediment Activity) γ-ray detection system was used for field measurements. The radium concentrations were then used with soil parameters to obtain the radon flux using different approaches such as the IAEA (International Atomic Energy Agency) formula. Another technique the MEDUSA Laboratory Technique (MELT) was developed to map radon exhalation based on (1) recognising that radon exhalation does not affect (40)K and (232)Th activity concentrations and (2) that the ratio of the activity concentration of the field (MEDUSA) to the laboratory (HPGe) for (238)U and (40)K or (238)U and (232)Th will give a measure of the radon exhalation at a particular location in the dump. The average, normalised radon flux was found to be 0.12 ± 0.02 Bq m(-2) s(-1) for the mine dump.

  20. Skeletal sup 210 Pb from inhalation of sup 222 Rn and its decay products

    SciTech Connect

    Keane, A.T.; Schlenker, R.A.; Stebbings, J.H.

    1990-01-01

    Concern about health effects of radon and its decay products has recently broadened to include the potential role of radon in the causation of myeloid leukemia, multiple myeloma, and melanoma, kidney cancer, and certain childhood cancers. Description of the distribution of radon and its daughters in the skeleton and the marrow, and the dose delivered to red marrow, are of particular relevance. Our interest in a metabolic model for inhaled radon and radon decay products originated with an interest in the use of radioactivity measurement techniques in vivo to quantify the {sup 210}Pb activity of bone. In this paper we estimate the rates of transfer to body fluids of {sup 210}Pb originating from inhaled radon and radon decay products and the quantity of {sup 210}Pb deposited in compact and in cancellous bone for the ideal case of continuous exposure to a constant level of radon and its daughters. We review the contributions of ambient airborne {sup 210}Pb, diet, and active and passive smoking to skeletal levels of {sup 210}Pb, and finally, from the magnitude and the variability of the natural {sup 210}Pb content of the skeleton, we estimate the minimal rate of exposure to airborne radon and its decay products that is required to elevate the skeletal {sup 210}Pb content of an individual to a statistically significant level above the population mean skeletal {sup 210}Pb content derived from all the other environmental sources combined. 55 refs., 4 tabs.

  1. Preparation of gaseous CRMs from the primary system for (222)Rn activity measurement.

    PubMed

    Kim, B J; Kim, B C; Lee, K B; Lee, J M; Park, T S

    2016-03-01

    For disseminating the gaseous radon standard traceable to the KRISS primary system based on the defined solid angle counting method, two kinds of radon CRM (a glass ampule type and a stainless steel cylinder type) were developed. The activity of the CRM was certified by subtracting a residual activity from the measured activity by the primary system. After certification, the ampule CRM was used to calibrate a radon-monitoring instrument and the cylinder CRM to calibrate an HPGe system. We also improved the measurement procedure of the radon primary system. In a typical radon energy spectrum, the radon peak overlaps with the polonium peak. For more reliable and accurate measurement of radon activity, a fitting method was adopted for the evaluation of radon area in the alpha energy spectrum. The result of radon activity evaluated by using the fitting method is in good agreement with that by the previous integration method. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. 222RN AS AN INDICATOR OF NONAQUEOUS PHASE LIQUID CONTAMINATION IN GROUNDWATER. (R825689C058)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. INNOVATIVE EASY-TO-USE PASSIVE TECHNIQUE FOR 222RN AND 220RN DECAY PRODUCT DETECTION.

    PubMed

    Mishra, Rosaline; Rout, R; Prajith, R; Jalalluddin, S; Sapra, B K; Mayya, Y S

    2016-10-01

    The decay products of radon and thoron are essentially the radioisotopes of polonium, bismuth and lead, and are solid particulates, which deposit in different parts of the respiratory tract upon inhalation, subsequently emitting high-energy alpha particles upon their radioactive decay. Development of passive deposition-based direct progeny sensors known as direct radon and thoron progeny sensors have provided an easy-to-use technique for time-integrated measurements of the decay products only. These dosemeters are apt for large-scale population dosimetry to assign inhalation doses to the public. The paper gives an insight into the technique, the calibration, comparison with the prevalently used active grab filter paper sampling technique, alpha track diameter analysis in these progeny sensors, progeny deposition velocity measurements carried out using these detector systems in the indoor as well as outdoor environment, and applications of these sensors for time-integrated unattached fraction estimation. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Low background counting of 222Rn, 220Rn and 219Rn with electrostatic counters

    NASA Astrophysics Data System (ADS)

    Mong, Brian; EXO-200 Collaboration; nEXO Collaboration

    2014-09-01

    The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. Supported by NSERC Project Grants ``Search for Double Beta Decay with EXO.''

  5. Using {sup 222}Rn as a tracer of geophysical processes in underground environments

    SciTech Connect

    Lacerda, T.; Anjos, R. M.; Silva, A. A. R. da; Yoshimura, E. M.

    2014-11-11

    Radon levels in two old mines in San Luis, Argentina, are reported and analyzed. These mines are today used for touristic visitation. Our goal was to assess the potential use of such radioactive noble gas as tracer of geological processes in underground environments. CR-39 nuclear track detectors were used during the winter and summer seasons. The findings show that the significant radon concentrations reported in this environment are subject to large seasonal modulations, due to the strong dependence of natural ventilation on the variations of outside temperature. The results also indicate that radon pattern distribution appear as a good method to localize unknown ducts, fissures or secondary tunnels in subterranean environments.

  6. 222RN AS AN INDICATOR OF NONAQUEOUS PHASE LIQUID CONTAMINATION IN GROUNDWATER. (R825689C058)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  7. Using 222Rn as a tracer of geophysical processes in underground environments

    NASA Astrophysics Data System (ADS)

    Lacerda, T.; Anjos, R. M.; Valladares, D. L.; da Silva, A. A. R.; Rizzotto, M.; Velasco, H.; de Rosas, J. P.; Ayub, J. Juri; Yoshimura, E. M.

    2014-11-01

    Radon levels in two old mines in San Luis, Argentina, are reported and analyzed. These mines are today used for touristic visitation. Our goal was to assess the potential use of such radioactive noble gas as tracer of geological processes in underground environments. CR-39 nuclear track detectors were used during the winter and summer seasons. The findings show that the significant radon concentrations reported in this environment are subject to large seasonal modulations, due to the strong dependence of natural ventilation on the variations of outside temperature. The results also indicate that radon pattern distribution appear as a good method to localize unknown ducts, fissures or secondary tunnels in subterranean environments.

  8. [Measurement of exhaled nitric oxide in healthy Chinese].

    PubMed

    Zhang, Luo; Luo, Xue-rui; Liu, Cheng-yao; Zhao, Yan; Han, De-min

    2009-04-01

    To obtain the normal values of nitric oxide (NO) exhaled through nose and mouth in healthy Chinese adults by measuring exhaled NO and analyzing the influencing factors. Eighty healthy Chinese adults were recruited, including 20 males and 60 females. The age ranged from 18 to 44 years old. Chemiluminescence analyzer (NIOX) was used to obtain the values of exhaled NO through nose and mouth. The relativity between NO and gender, age, height, body mass index, time, ambient NO were analyzed with Multiple linear regression and correlation. Exhaled NO values were (17+/-8)x10(-9) and correlated significantly with height. Regression equation: Y (exhaled nitric oxide)=-58.524+0.457X (height, cm), t=-2.985, P<0.01. Transnasal NO values were (819+/-211)x10(-9) and correlated significantly with age and gender. Regression equation: Y (nasal nitric oxide)=760.245+9.417X1(age)-111.222X2(gender), t=5.188, P<0.01. Exhaled NO normal values were 17x10(-9) and Transnasal NO normal values were 819x10(-9). Exhaled NO correlated positively with height. Transnasal NO correlated positively with age and negatively with gender.

  9. Fractional exhaled nitric oxide-measuring devices: technology update

    PubMed Central

    Maniscalco, Mauro; Vitale, Carolina; Vatrella, Alessandro; Molino, Antonio; Bianco, Andrea; Mazzarella, Gennaro

    2016-01-01

    The measurement of exhaled nitric oxide (NO) has been employed in the diagnosis of specific types of airway inflammation, guiding treatment monitoring by predicting and assessing response to anti-inflammatory therapy and monitoring for compliance and detecting relapse. Various techniques are currently used to analyze exhaled NO concentrations under a range of conditions for both health and disease. These include chemiluminescence and electrochemical sensor devices. The cost effectiveness and ability to achieve adequate flexibility in sensitivity and selectivity of NO measurement for these methods are evaluated alongside the potential for use of laser-based technology. This review explores the technologies involved in the measurement of exhaled NO. PMID:27382340

  10. Radon exhalation from building materials used in Libya

    NASA Astrophysics Data System (ADS)

    Saad, A. F.; Al-Awami, Hend H.; Hussein, N. A.

    2014-08-01

    Radon exhalation rates have been determined for various different samples of domestic and imported building materials available in the Libyan market for home construction and interior decoration. Radon exhalation rates were measured by the sealed-can technique based on CR-39 nuclear track detectors (NTDs). The results show that radon exhalation rates from some imported building materials used as foundations and for decoration are extremely high, and these samples are the main sources of indoor radon emanation. Radium contents and annual effective doses have also been estimated.

  11. USE OF EXHALED BREATH CONDENSATE IN A HUMAN EXPOSURE STUDY

    EPA Science Inventory

    Exhaled breath condensate (EBC) is a noninvasive, repeatable collection technique to sample biomarkers of lung inflammation, oxidative stress, and environmental exposure. It is unclear whether EBC is an effective tool in human environmental exposure studies with multi-day samplin...

  12. On the exhalation rate of radon by man

    SciTech Connect

    Rundo, J.; Markun, F.; Plondke, N.J.

    1990-01-01

    This paper describes some aspects of the exhalation rate of radon by man which may be relevant to its internal dosimetry and, therefore, to possible radiobiological consequences. Prolonged exposure of a person to radon results in a reservoir or radon dissolved in body fat and fluids. If the person then moves to an environment with a lower radon concentration, there is a net exhalation of radon and the initial exhalation rate depends on the radon concentration in the first environment. This is demonstrated for seven persons whose houses contained radon at concentrations varying from 10 Bq m{sup {minus}3} to almost 1000 Bq m{sup {minus}3}. About one hour after leaving the house, the subjects' average exhalation rate of radon, expressed as the equivalent volume of house air per unit time, was 236 mL min{sup {minus}1}. 4 refs., 4 figs., 2 tabs.

  13. MEASUREMENT METHOD FOR VOLATILE METABOLIC BIOMARKERS IN EXHALED BREATH CONDENSATE

    EPA Science Inventory

    EPA is developing biomarker methodology to interpret spot biological measurements and their linkage to previous environmental pollutants exposures for individuals. This work explores the use of a promising biological media, exhaled breath condensate (EBC), which contains trapped...

  14. USE OF EXHALED BREATH CONDENSATE IN A HUMAN EXPOSURE STUDY

    EPA Science Inventory

    Exhaled breath condensate (EBC) is a noninvasive, repeatable collection technique to sample biomarkers of lung inflammation, oxidative stress, and environmental exposure. It is unclear whether EBC is an effective tool in human environmental exposure studies with multi-day samplin...

  15. Exhaled breath hydrogen cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis.

    PubMed

    Gilchrist, Francis J; Belcher, John; Jones, Andrew M; Smith, David; Smyth, Alan R; Southern, Kevin W; Španěl, Patrik; Webb, A Kevin; Lenney, Warren

    2015-10-01

    Hydrogen cyanide is readily detected in the headspace above Pseudomonas aeruginosa cultures and in the breath of cystic fibrosis (CF) patients with chronic (P. aeruginosa) infection. We investigated if exhaled breath HCN is an early marker of P. aeruginosa infection. 233 children with CF who were free from P. aeruginosa infection were followed for 2 years. Their median (interquartile range) age was 8.0 (5.0-12.2) years. At each study visit, an exhaled breath sample was collected for hydrogen cyanide analysis. In total, 2055 breath samples were analysed. At the end of the study, the hydrogen cyanide concentrations were compared to the results of routine microbiology surveillance. P. aeruginosa was isolated from 71 children during the study with an incidence (95% CI) of 0.19 (0.15-0.23) cases per patient-year. Using a random-effects logistic model, the estimated odds ratio (95% CI) was 3.1 (2.6-3.6), which showed that for a 1- ppbv increase in exhaled breath hydrogen cyanide, we expected a 212% increase in the odds of P. aeruginosa infection. The sensitivity and specificity were estimated at 33% and 99%, respectively. Exhaled breath hydrogen cyanide is a specific biomarker of new P. aeruginosa infection in children with CF. Its low sensitivity means that at present, hydrogen cyanide cannot be used as a screening test for this infection.

  16. Exhaled breath hydrogen cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis

    PubMed Central

    Belcher, John; Jones, Andrew M.; Smith, David; Smyth, Alan R.; Southern, Kevin W.; Španěl, Patrik; Webb, A. Kevin; Lenney, Warren

    2015-01-01

    Hydrogen cyanide is readily detected in the headspace above Pseudomonas aeruginosa cultures and in the breath of cystic fibrosis (CF) patients with chronic (P. aeruginosa) infection. We investigated if exhaled breath HCN is an early marker of P. aeruginosa infection. 233 children with CF who were free from P. aeruginosa infection were followed for 2 years. Their median (interquartile range) age was 8.0 (5.0–12.2) years. At each study visit, an exhaled breath sample was collected for hydrogen cyanide analysis. In total, 2055 breath samples were analysed. At the end of the study, the hydrogen cyanide concentrations were compared to the results of routine microbiology surveillance. P. aeruginosa was isolated from 71 children during the study with an incidence (95% CI) of 0.19 (0.15–0.23) cases per patient-year. Using a random-effects logistic model, the estimated odds ratio (95% CI) was 3.1 (2.6–3.6), which showed that for a 1- ppbv increase in exhaled breath hydrogen cyanide, we expected a 212% increase in the odds of P. aeruginosa infection. The sensitivity and specificity were estimated at 33% and 99%, respectively. Exhaled breath hydrogen cyanide is a specific biomarker of new P. aeruginosa infection in children with CF. Its low sensitivity means that at present, hydrogen cyanide cannot be used as a screening test for this infection. PMID:27730156

  17. Radon exhalation from building materials for decorative use.

    PubMed

    Chen, Jing; Rahman, Naureen M; Abu Atiya, Ibrahim

    2010-04-01

    Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m(-2) d(-1). Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m(-2) d(-1) for slate tiles and 42 Bq m(-2) d(-1) for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m(-2) d(-1), it would contribute only 18 Bq m(-3) to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.

  18. Oxygenation using tidal volume breathing after maximal exhalation.

    PubMed

    Baraka, Anis S; Taha, Samar K; El-Khatib, Mohamad F; Massouh, Faraj M; Jabbour, Dima G; Alameddine, Mahmoud M

    2003-11-01

    We compared, in volunteers, the oxygenation achieved by tidal volume breathing (TVB) over a 3-min period after maximal exhalation with that achieved by TVB alone. Twenty-three healthy volunteers underwent the two breathing techniques in a randomized order. A circle absorber system with an oxygen flow of 10 L/min was used. The end-expiratory oxygen concentration (EEO(2)) was monitored at 15-s intervals up to 3 min. TVB after maximal exhalation produced EEO(2) values of 68% +/- 5%, 75% +/- 5%, and 79% +/- 4% at 30, 45, and 60 s, respectively, which were significantly larger (P < 0.05) than the corresponding values obtained with TVB alone (58% +/- 5%, 66% +/- 6%, and 71% +/- 5%, respectively). In both techniques, the EEO(2) increased exponentially, with time constants of 35 s during TVB after maximal exhalation versus 58 s during TVB without prior maximal exhalation. In conclusion, maximal exhalation before TVB can hasten preoxygenation by decreasing the nitrogen content of the functional residual capacity, with a consequent increase of EEO(2) to approximately 70% in 30 s and 80% in 60 s. Oxygenation by using maximal exhalation before tidal volume breathing produced a significantly faster increase in end-expiratory oxygen concentration than oxygenation with tidal volume breathing alone.

  19. Exhaled pH, exhaled nitric oxide, and induced sputum cellularity in obese patients with obstructive sleep apnea syndrome.

    PubMed

    Carpagnano, Giovanna E; Spanevello, Antonio; Sabato, Roberto; Depalo, Annarita; Turchiarelli, Viviana; Foschino Barbaro, Maria Pia

    2008-01-01

    Airway inflammation plays an important role in obstructive sleep apnea syndrome as well as in obesity. Increasingly, researchers are studying airway inflammation noninvasively and are studying the new markers of airways inflammation. The aim of this study was to measure pH in the exhaled breath condensate (EBC), the exhaled nitric oxide (NO), and the inflammatory cell profile in the induced sputum of obese patients with and without obstructive sleep apnea syndrome (OSAS). The pH in EBC, the exhaled NO, and the induced sputum cells were measured in 30 obese patients with OSAS (OOs), in 20 obese patients without OSAS (ONOs), and in 10 healthy patients (HPs). Levels of pH in EBC were lower in OOs and in ONOs than in HPs. Furthermore, the concentrations of exhaled NO and the percentages of neutrophils in the induced sputum were greater in OOs and in ONOs than in HPs. No significant differences were found between OO and ONO for other measurements of airway inflammation. This study shows the presence of airway's inflammation in obese patients with and without OSAS and indicates that the "exhaled acidopnea" as well as exhaled NO and sputum neutrophils are good tools to measure airway inflammation in these subjects.

  20. A process-based 222radon flux map for Europe and its comparison to long-term observations

    NASA Astrophysics Data System (ADS)

    Karstens, U.; Schwingshackl, C.; Schmithüsen, D.; Levin, I.

    2015-11-01

    Detailed 222radon (222Rn) flux maps are an essential pre-requisite for the use of radon in atmospheric transport studies. Here we present a high-resolution 222Rn flux map for Europe, based on a parameterization of 222Rn production and transport in the soil. The 222Rn exhalation rate is parameterized based on soil properties, uranium content, and modelled soil moisture from two different land-surface reanalysis data sets. Spatial variations in exhalation rates are primarily determined by the uranium content of the soil, but also influenced by soil texture and local water-table depth. Temporal variations are related to soil moisture variations as the molecular diffusion in the unsaturated soil zone depends on available air-filled pore space. The implemented diffusion parameterization was tested against campaign-based 222Rn soil profile measurements. Monthly 222Rn exhalation rates from European soils were calculated with a nominal spatial resolution of 0.083° × 0.083° and compared to long-term direct measurements of 222Rn exhalation rates in different areas of Europe. The two realizations of the 222Rn flux map, based on the different soil moisture data sets, both realistically reproduce the observed seasonality in the fluxes but yield considerable differences for absolute flux values. The mean 222Rn flux from soils in Europe is estimated to be 10 mBq m-2 s-1 (ERA-Interim/Land soil moisture) or 15 mBq m-2 s-1 (GLDAS (Global Land Data Assimilation System) Noah soil moisture) for the period 2006-2010. The corresponding seasonal variations with low fluxes in winter and high fluxes in summer range in the two realizations from ca. 7 to ca. 14 mBq m-2 s-1 and from ca. 11 to ca. 20 mBq m-2 s-1, respectively. These systematic differences highlight the importance of realistic soil moisture data for a reliable estimation of 222Rn exhalation rates. Comparison with observations suggests that the flux estimates based on the GLDAS Noah soil moisture model on average better

  1. Origin of Exhaled Breath Particles from Healthy and Human Rhinovirus-Infected Subjects

    PubMed Central

    Brain, Joseph; Houseman, E. Andres; Gern, James; Milton, Donald K.

    2011-01-01

    Abstract Background Exhaled breath studies suggest that humans exhale fine particles during tidal breathing, but little is known of their physical origin in the respiratory system during health or disease. Methods Particles generated by 3 healthy and 16 human rhinovirus (HRV)-infected subjects were counted using an optical particle counter with nominal diameter-size bins ranging between 0.3 and 10 μm. Data were collected from HRV-infected subjects during tidal breathing. In addition, data from healthy subjects were collected during coughs, swallows, tidal breathing, and breathing to total lung capacity (TLC) and residual volume (RV). Using general additive models, we graphed exhaled particle concentration versus airflow during exhalation. Exhaled particles were collected from expired air on gelatin filters and analyzed for HRV via quantitative PCR. Results HRV-infected subjects exhaled from 0.1 to 7200 particles per liter of exhaled air during tidal breathing (geometric mean = 32 part/L). A small fraction (24%) of subjects exhaled most (81%) of the particles measured and 82% of particles detected were 0.300–0.499 μm. Minute ventilation, maximum airflow during exhalation, and forced expiratory volume 1 second (FEV1 % predicted) were positively correlated with particle production. No human rhinovirus was detected in exhaled breath samples. Three healthy subjects exhaled less than 100 particles per liter of exhaled air during tidal breathing and increased particle concentrations more with exhalation to RV than with coughing, swallowing, or rapid exhalation. Conclusions Submicron particles were detected in the exhaled breath of healthy and HRV-infected subjects. Particle concentrations were correlated with airflow during the first half of exhalation, and peaked at the end of exhalation, indicating both lower and upper airways as particle sources. The effect of breathing maneuver suggested a major contribution from lower airways, probably the result of

  2. Analysis of exhaled breath by laser detection

    NASA Astrophysics Data System (ADS)

    Thrall, Karla D.; Toth, James J.; Sharpe, Steven W.

    1996-04-01

    The goal of our work is two fold: (1) to develop a portable rapid laser based breath analyzer for monitoring metabolic processes, and (2) predict these metabolic processes through physiologically based pharmacokinetic (PBPK) modeling. Small infrared active molecules such as ammonia, carbon monoxide, carbon dioxide, methane and ethane are present in exhaled breath and can be readily detected by laser absorption spectroscopy. In addition, many of the stable isotopomers of these molecules can be accurately detected, making it possible to follow specific metabolic processes. Potential areas of applications for this technology include the diagnosis of certain pathologies (e.g. Helicobacter Pylori infection), detection of trauma due to either physical or chemical causes and monitoring nutrient uptake (i.e., malnutrition). In order to understand the origin and elucidate the metabolic processes associated with these small molecules, we are employing physiologically based pharmacokinetic (PBPK) models. A PBPK model is founded on known physiological processes (i.e., blood flow rates, tissue volumes, breathing rate, etc.), chemical-specific processes (i.e., tissue solubility coefficients, molecular weight, chemical density, etc.), and on metabolic processes (tissue site and rate of metabolic biotransformation). Since many of these processes are well understood, a PBPK model can be developed and validated against the more readily available experimental animal data, and then by extrapolating the parameters to apply to man, the model can predict chemical behavior in humans.

  3. Influence of the porosity on the ²²²Rn exhalation rate of concrete.

    PubMed

    de Jong, Peter; van Dijk, Willem; de Rooij, Mario

    2011-02-01

    The composition of 23 concrete mixtures was varied in five separate series to evaluate the influence of porosity on the ²²²Rn exhalation rate. In each series, a range in porosities is obtained by varying (1) the amount of cement, (2) type of cement (Portland or blast furnace slag cement), (3) the amount of water at a fixed cement level, (4) addition of an air entraining agent, or (5) the amount of recycled aggregates. The porosities ranged from 1% to 16%. The ²²²Rn exhalation rate is normalized to the ²²⁶Ra activity concentration and expressed as the ²²²Rn release factor to eliminate the effect of differences in ²²⁶Ra activity concentrations among the various concrete mixtures. Since most ²²²Rn originates from the cement, a ²²²Rn release factor based on the amount of ²²⁶Ra introduced by the cements appeared to be more adequate. Although the methods to attain the porosities in the concrete mixtures differ widely, this cement-related factor corresponds well with the capillary porosity of the mixtures. Since the water-to-cement ratio of the fresh paste is a good indicator of the capillary porosity, this is the guiding factor in the fabrication of concretes low in ²²²Rn exhalation. The lower the water-to-cement ratio, the less capillary pore area will be available from which ²²²Rn can emanate from the mineral matrix into the pore system. The good correlation between the cement-based ²²²Rn release factor and literature data on the internal capillary pore area support the results of this study.

  4. 42 CFR 84.120 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Inhalation valves shall be designed and constructed to prevent excessive exhaled air from adversely affecting cartridges, canisters, and filters. (c) Exhalation valves shall be protected against external influence, and designed and constructed to prevent inward leakage of contaminated air. ...

  5. 42 CFR 84.182 - Exhalation valve leakage test; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-Powered Air-Purifying Particulate Respirators § 84.182 Exhalation valve leakage test; minimum requirements. (a) Dry exhalation valves and valve seats will be subjected to a suction of 25 mm. water-column...

  6. 42 CFR 84.182 - Exhalation valve leakage test; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-Powered Air-Purifying Particulate Respirators § 84.182 Exhalation valve leakage test; minimum requirements. (a) Dry exhalation valves and valve seats will be subjected to a suction of 25 mm. water-column...

  7. [Exogenic proteins in the human exhaled breath condensate].

    PubMed

    Kurova, V S; Kononikhin, A S; Sakharov, D A; Popov, I A; Larina, I M; Tonevitskiĭ, A G; Varfolomeev, S D; Nikolaev, E N

    2011-01-01

    The analysis of the protein composition of exhaled breath to diagnose diseases of the respiratory system raises a problem of differentiation proteins of expressed in the tissues of the lungs and respiratory tract (endogenous) and got in the respiratory system from the ambient air in the process of respiration (exogenous). In this work an attempt was made to estimate a set of exhaled exogenic proteins by mass spectrometry coupled with nanoflow HPLC. Six-month isolation of healthy donors indoors with air cleaned of dust leads to removal from the spectrum of exhaled proteins of some keratins that are considered therefore to be exogenic. Non-keratin proteins may also circulate between the ambient air and human respiratory ways, but their concentration appears to be significantly lower the keratin concentrations (especially epidermis keratin). Among non-keratins dermcidin seems to be the most significant exogenic protein of exhaled air. The conclusion of the diagnostic value of exhaled proteins can be done only after careful comparison of the results of quantitative and qualitative analysis of their composition in norm and pathology for a statistically significant sample of donors.

  8. Exhaled breath condensate: a new method for lung disease diagnosis.

    PubMed

    Cepelak, Ivana; Dodig, Slavica

    2007-01-01

    Analysis of exhaled breath composition in lung disease patients can indirectly point to biochemical changes that occur in the fluid lining airway surfaces. The parameters of redox and acid-base changes, and of inflammatory changes relevant in the pathogenesis of most pulmonary diseases are currently most widely determined in exhaled breath condensate. The collection of exhaled breath condensate is a safe, non-invasive, easy and simple diagnostic procedure that is suitable for longitudinal studies and applicable in patients of all age groups, irrespective of the disease severity. In spite of many scientific studies involving lung disease patients, methodology for exhaled breath condensate collection and analysis has not yet been realized for daily utilization. Additional studies of the exact origin of condensate constituents and standardization of the overall analytical process, including collection, storage, analysis and result interpretation, are needed. Irrespective of these limitations, further investigation of this sample type is fully justified by the fact that classical specimens used in the management of pulmonary disease are either obtained by invasive procedures (e.g., induced sputum, biopsy, bronchoalveolar lavage) or cannot provide appropriate information (e.g., urine, serum). Analysis of exhaled breath condensate in the future might contribute significantly to our understanding of the physiological and pathophysiological processes in lungs, to early detection, diagnosis and follow up of disease progression, and to evaluation of therapeutic response.

  9. The Clinical Potential of Exhaled Breath Analysis For Diabetes Mellitus

    PubMed Central

    Minh, Timothy Do Chau; Blake, Donald Ray; Galassetti, Pietro Renato

    2012-01-01

    Summary Various compounds in present human breath have long been loosely associated with pathological states (including acetone smell in uncontrolled diabetes). Only recently, however, the precise measurement of exhaled volatile organic compounds (VOCs) and aerosolized particles was made possible at extremely low concentrations by advances in several analytical methodologies, described in detail in the international literature and each suitable for specific subsets of exhaled compounds. Exhaled gases may be generated endogenously (in the pulmonary tract, blood, or peripheral tissues), as metabolic byproducts of human cells or colonizing micro-organisms, or may be inhaled as atmospheric pollutants; growing evidence indicates that several of these molecules have distinct cell-to-cell signaling functions. Independent of origin and physiological role, exhaled VOCs are attractive candidates as biomarkers of cellular activity/metabolism, and could be incorporated in future non-invasive clinical testing devices. Indeed, several recent studies reported altered exhaled gas profiles in dysmetabolic conditions and relatively accurate predictions of glucose concentrations, at least in controlled experimental conditions, for healthy and diabetic subjects over a broad range of glycemic values. Optimization of this methodology and validation in large-scale trials under a wider range of conditions is needed to determine its true potential to transition into practical clinical use. PMID:22410396

  10. Modelling the risk of airborne infectious disease using exhaled air.

    PubMed

    Issarow, Chacha M; Mulder, Nicola; Wood, Robin

    2015-05-07

    In this paper we develop and demonstrate a flexible mathematical model that predicts the risk of airborne infectious diseases, such as tuberculosis under steady state and non-steady state conditions by monitoring exhaled air by infectors in a confined space. In the development of this model, we used the rebreathed air accumulation rate concept to directly determine the average volume fraction of exhaled air in a given space. From a biological point of view, exhaled air by infectors contains airborne infectious particles that cause airborne infectious diseases such as tuberculosis in confined spaces. Since not all infectious particles can reach the target infection site, we took into account that the infectious particles that commence the infection are determined by respiratory deposition fraction, which is the probability of each infectious particle reaching the target infection site of the respiratory tracts and causing infection. Furthermore, we compute the quantity of carbon dioxide as a marker of exhaled air, which can be inhaled in the room with high likelihood of causing airborne infectious disease given the presence of infectors. We demonstrated mathematically and schematically the correlation between TB transmission probability and airborne infectious particle generation rate, ventilation rate, average volume fraction of exhaled air, TB prevalence and duration of exposure to infectors in a confined space.

  11. Regional diffusing capacity in normal lungs during a slow exhalation.

    PubMed

    MacIntyre, N R; Nadel, J A

    1982-06-01

    From an analysis of carbon monoxide uptake and xenon-133 distribution after two bolus inhalations of these gases, we calculated regional diffusing capacity in the upper and lower volume halves of the lungs during the middle 60% of an exhaled vital capacity in five seated normal subjects. We found that the regional diffusing capacity of the upper half of the lungs was 11.6 +/- 4.2 (mean +/- SD) ml.min-1.Torr-1 and that the regional diffusing capacity of the lower half of the lungs was 24.4 +/- 2.4 ml.min-1.Torr-1 after 25% of the vital capacity had been exhaled. These values remained relatively constant as lung volume decreased from 25 to 75% of the exhaled vital capacity. Diffusing capacity in the upper half of the lungs ranged from 9.4 to 12.4 ml.min-1.Torr-1 during exhalation, and in the lower half of the lungs from 21.0 to 28.6 ml.min-1.Torr-1 during exhalation. These results suggest that total lung diffusing capacity remains relatively constant over this midrange of lung volumes and that this occurs because the regional diffusing capacities in both the upper and lower halves of the lungs remain relatively constant.

  12. Metabolite Content Profiling of Bottlenose Dolphin Exhaled Breath

    PubMed Central

    2014-01-01

    Changing ocean health and the potential impact on marine mammal health are gaining global attention. Direct health assessments of wild marine mammals, however, is inherently difficult. Breath analysis metabolomics is a very attractive assessment tool due to its noninvasive nature, but it is analytically challenging. It has never been attempted in cetaceans for comprehensive metabolite profiling. We have developed a method to reproducibly sample breath from small cetaceans, specifically Atlantic bottlenose dolphins (Tursiops truncatus). We describe the analysis workflow to profile exhaled breath metabolites and provide here a first library of volatile and nonvolatile compounds in cetacean exhaled breath. The described analytical methodology enabled us to document baseline compounds in exhaled breath of healthy animals and to study changes in metabolic content of dolphin breath with regard to a variety of factors. The method of breath analysis may provide a very valuable tool in future wildlife conservation efforts as well as deepen our understanding of marine mammals biology and physiology. PMID:25254551

  13. Slower rise of exhaled breath temperature in cystic fibrosis.

    PubMed

    Bade, Geetanjali; Gupta, Sumita; Kabra, Sushil Kumar; Talwar, Anjana

    2015-02-01

    To measure exhaled breath temperature in patients with cystic fibrosis. 17 patients (6-18 years) with cystic fibrosis and 15 age- and gender-matched healthy controls were recruited in this cross sectional study. Exhaled breath temperature was measured in subjects recruited in both the groups with a device X-halo and analyzed as plateau temperature achieved and rate of temperature rise. Patients with cystic fibrosis showed no significant difference in plateau temperature [34.4(32.3-34.6) versus 33.9 (33.0-34.4)oC; P=0.35] while mean (SEM.) rate of temperature rise was significantly less in patients [0.09 (0.01) versus 0.14 (0.02) ƼC/s ; P=0.04] as compared to controls. There was a slower rise of exhaled breath temperature in patients with cystic fibrosis whereas plateau temperature was not significantly different from controls.

  14. Design of the exhale airway stents for emphysema (EASE) trial: an endoscopic procedure for reducing hyperinflation.

    PubMed

    Shah, Pallav L; Slebos, Dirk-Jan; Cardoso, Paulo F G; Cetti, Edward J; Sybrecht, Gerhard W; Cooper, Joel D

    2011-01-07

    Airway Bypass is a catheter-based, bronchoscopic procedure in which new passageways are created that bypass the collapsed airways, enabling trapped air to exit the lungs. The Exhale Airway Stents for Emphysema (EASE) Trial was designed to investigate whether Exhale® Drug-Eluting Stents, placed in new passageways in the lungs, can improve pulmonary function and reduce breathlessness in severely hyperinflated, homogeneous emphysema patients (NCT00391612). The multi-center, randomized, double-blind, sham-controlled trial design was posted on http://www.clinicaltrials.gov in October 2006. Because Bayesian statistics are used for the analysis, the proposed enrollment ranged from 225 up to 450 subjects at up to 45 institutions. Inclusion criteria are: high resolution CT scan with evidence of homogeneous emphysema, post-bronchodilator pulmonary function tests showing: a ratio of FEV1/FVC < 70%, FEV1 ≤ 50% of predicted or FEV1 < 1 liter, RV/TLC ≥ 0.65 at screening, marked dyspnea score ≥ 2 on the modified Medical Research Council scale of 0-4, a smoking history of at least 20 pack years and stopped smoking for at least 8 weeks prior to enrollment. Following 16 to 20 supervised pulmonary rehabilitation sessions, subjects were randomized 2:1 to receive either a treatment (Exhale® Drug-Eluting Stent) or a sham bronchoscopy. A responder analysis will evaluate the co-primary endpoints of an FVC improvement ≥ 12% of the patient baseline value and modified Medical Research Council dyspnea scale improvement (reduction) ≥ 1 point at the 6-month follow-up visit. If through the EASE Trial, Airway Bypass is shown to improve pulmonary function and reduce dyspnea while demonstrating an acceptable safety profile, then homogeneous patients will have a minimally invasive treatment option with meaningful clinical benefit. ClinicalTrials.gov: NCT00391612.

  15. Design of the exhale airway stents for emphysema (EASE) trial: an endoscopic procedure for reducing hyperinflation

    PubMed Central

    2011-01-01

    Background Airway Bypass is a catheter-based, bronchoscopic procedure in which new passageways are created that bypass the collapsed airways, enabling trapped air to exit the lungs. The Exhale Airway Stents for Emphysema (EASE) Trial was designed to investigate whether Exhale® Drug-Eluting Stents, placed in new passageways in the lungs, can improve pulmonary function and reduce breathlessness in severely hyperinflated, homogeneous emphysema patients (NCT00391612). Methods/Design The multi-center, randomized, double-blind, sham-controlled trial design was posted on http://www.clinicaltrials.gov in October 2006. Because Bayesian statistics are used for the analysis, the proposed enrollment ranged from 225 up to 450 subjects at up to 45 institutions. Inclusion criteria are: high resolution CT scan with evidence of homogeneous emphysema, post-bronchodilator pulmonary function tests showing: a ratio of FEV1/FVC < 70%, FEV1≤50% of predicted or FEV1 < 1 liter, RV/TLC≥0.65 at screening, marked dyspnea score ≥2 on the modified Medical Research Council scale of 0-4, a smoking history of at least 20 pack years and stopped smoking for at least 8 weeks prior to enrollment. Following 16 to 20 supervised pulmonary rehabilitation sessions, subjects were randomized 2:1 to receive either a treatment (Exhale® Drug-Eluting Stent) or a sham bronchoscopy. A responder analysis will evaluate the co-primary endpoints of an FVC improvement ≥12% of the patient baseline value and modified Medical Research Council dyspnea scale improvement (reduction) ≥1 point at the 6-month follow-up visit. Discussion If through the EASE Trial, Airway Bypass is shown to improve pulmonary function and reduce dyspnea while demonstrating an acceptable safety profile, then homogeneous patients will have a minimally invasive treatment option with meaningful clinical benefit. Trial Registration ClinicalTrials.gov: NCT00391612 PMID:21214899

  16. Influence of ventilatory settings on exhaled nitric oxide during high frequency oscillatory ventilation.

    PubMed

    Yuh, Yeong-Seng; Hua, Yi-Ming

    2009-08-01

    Nitric oxide (NO), which is produced in the lower airways, diffuses from cells into the air space and can be measured in exhaled air. The influence of high frequency oscillatory ventilation on the production of exhaled NO (eNO) has not been thoroughly studied. The objectives of this study are to establish an animal model for evaluation of lower airway NO and to evaluate settings in terms of frequency, mean airway pressure (MAP), amplitude pressure (amplitude), and inspiratory time ratio (t(I)/t(E)) during high frequency oscillatory ventilation on the production of eNO. An observational animal study was performed on 12 female New Zealand White rabbits, which were anesthetized, tracheotomized and ventilated using a SensorMedics 3100A HFOV ventilator (SM3100A). The concentration of NO in exhaled gas was measured by chemiluminescence continuously from the nose and the side hole of the adaptor of endotracheal tube. The individual effects of the respiratory settings were evaluated. The results were analyzed by paired t-test or by the generalized estimating equation method. We found that the lower airway was the main source of the eNO, that amplitude, MAP, and t(I)/t(E) were positively correlated with the level of eNO and that frequency was negatively correlated with the level of eNO. These findings fit the stretch theory for the production of endogenous NO. Monitoring of eNO during HFOV may provide insights into lung mechanics and ventilation efficiency and be used in the future as a guide during clinical practice.

  17. Upper mantle-derived free gas exhalations in central Europe - an isotope study

    NASA Astrophysics Data System (ADS)

    Braeuer, K.; Kaempf, H.; Niedermann, S.; Strauch, G.; Weise, S. M.

    2003-04-01

    The results of geochemical mapping (about 100 locations) of free gas exhalations in the western Eger Rift (Czech-German border region) are compared with data of free gas exhalations from the surroundings of the Laacher See (East Eifel, Germany) and Le Mont Dore (Massif Central, France). In the western Eger Rift, three gas exhalation centres characterized by high gas flux (> 85 m^3 h-1), CO_2 concentrations > 99 vol. -%, δ13C between -2 and -4 per mil, and ^3He/^4He ratios up to 6 R_a could be distinguished. CO_2-rich gases consist of mantle-derived components with only small admixtures of dissolved air due to sampling after passing a water phase. The scatter in δ13C values of CO_2-rich gases is due to isotope fractionation between gaseous CO_2, dissolved CO_2 and HCO_3, respectively. As a result of long-term monitoring studies at four locations in the western Eger Rift, the natural variation range of the gas and isotope composition could be evaluated and as a consequence of numerous data sets reliable δ15N mean values could be specified. At the Bublak mofette (NW Bohemia), the transport velocity in the upper crust is estimated at about 400 m/d. The Bublak CO_2 is enriched in 13C (δ13C ≈ -2 per mil) relative to MORB values and its CO_2/^3He is ˜6.5x10^9. In addition to the ^3He/^4He ratio of ≈ 5.9 R_a, which is in the range of values for European sub-continental mantle xeno-liths, also the uncorrected δ15N values (-3.2±0.7, n=16) show an upper mantle signature. Corrected for air via O_2 contents and/or 40Ar/36Ar ratios, the 15N/14N ratios yield δ15N <= -5 per mil, corresponding to mantle-derived nitrogen contributions of about 50 %. The channel-like fluid supply at the Bublak mofette related with the high transport velocity indicates that its isotope ratios are not significantly altered during transport through the crust and represent probably the signature of the magmatic source in the European sub-continental mantle. Comparable distribution patterns of

  18. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that u...

  19. 42 CFR 84.123 - Exhalation valve leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks §...

  20. 42 CFR 84.123 - Exhalation valve leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks §...

  1. 42 CFR 84.123 - Exhalation valve leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks §...

  2. 42 CFR 84.123 - Exhalation valve leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks §...

  3. MEASUREMENTS OF AIR POLLUTANT BIOMARKERS WITH EXHALED BREATH TECHNIQUES

    EPA Science Inventory

    Use of exhaled breath condensate (EBC) has appeal as a noninvasive surrogate sample for lung-derived fluid. Additionally, EBC can be collected multiple times over the course of a study, unlike many other lung sampling techniques which can be performed fewer times. However validat...

  4. 42 CFR 84.123 - Exhalation valve leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks §...

  5. Radon exhalation rate of some building materials used in Egypt.

    PubMed

    Maged, A F; Ashraf, F A

    2005-09-01

    Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses, which are considered as one of the major sources of this gas in indoor environment, have been studied for exhalation rate of radon. Non-nuclear industries, such as coal fired power plants or fertilizer production facilities, generate large amounts of waste gypsum as by-products. Compared to other building materials waste gypsum from fertilizer production facilities (phosphogypsum) shows increased rates of radon exhalation. In the present, investigation solid state alpha track detectors, CR-39 plastic detectors, were used to measure the indoor radon concentration and the radon exhalation rates from some building materials used in Egypt. The indoor radon concentration and the radon exhalation rate ranges were found to be 24-55 Bq m(-3 )and 11-223 mBq m(-2) h(-1), respectively. The effective dose equivalent range for the indoor was found 0.6-1.4 mSv y(-1). The equilibrium factor between radon and its daughters increased with the increase of relative humidity.

  6. MEASUREMENTS OF AIR POLLUTANT BIOMARKERS WITH EXHALED BREATH TECHNIQUES

    EPA Science Inventory

    Use of exhaled breath condensate (EBC) has appeal as a noninvasive surrogate sample for lung-derived fluid. Additionally, EBC can be collected multiple times over the course of a study, unlike many other lung sampling techniques which can be performed fewer times. However validat...

  7. Radon exhalation rates from some soil samples of Kharar, Punjab

    SciTech Connect

    Mehta, Vimal; Singh, Tejinder Pal; Chauhan, R. P.; Mudahar, G. S.

    2015-08-28

    Radon and its progeny are major contributors in the radiation dose received by general population of the world. Because radon is a noble gas, a large portion of it is free to migrate away from radium. The primary sources of radon in the houses are soils and rocks source emanations, emanation from building materials, and entry of radon into a structure from outdoor air. Keeping this in mind the study of radon exhalation rate from some soil samples of the Kharar, Punjab has been carried out using Can Technique. The equilibrium radon concentration in various soil samples of Kharar area of district Mohali varied from 12.7 Bqm{sup −3} to 82.9 Bqm{sup −3} with an average of 37.5 ± 27.0 Bqm{sup −3}. The radon mass exhalation rates from the soil samples varied from 0.45 to 2.9 mBq/kg/h with an average of 1.4 ± 0.9 mBq/kg/h and radon surface exhalation rates varied from 10.4 to 67.2 mBq/m{sup 2}/h with an average of 30.6 ± 21.8 mBq/m{sup 2}/h. The radon mass and surface exhalation rates of the soil samples of Kharar, Punjab were lower than that of the world wide average.

  8. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that u...

  9. Noninvasive detection of lung cancer by analysis of exhaled breath

    PubMed Central

    2009-01-01

    Background Lung cancer is one of the leading causes of death in Europe and the western world. At present, diagnosis of lung cancer very often happens late in the course of the disease since inexpensive, non-invasive and sufficiently sensitive and specific screening methods are not available. Even though the CT diagnostic methods are good, it must be assured that "screening benefit outweighs risk, across all individuals screened, not only those with lung cancer". An early non-invasive diagnosis of lung cancer would improve prognosis and enlarge treatment options. Analysis of exhaled breath would be an ideal diagnostic method, since it is non-invasive and totally painless. Methods Exhaled breath and inhaled room air samples were analyzed using proton transfer reaction mass spectrometry (PTR-MS) and solid phase microextraction with subsequent gas chromatography mass spectrometry (SPME-GCMS). For the PTR-MS measurements, 220 lung cancer patients and 441 healthy volunteers were recruited. For the GCMS measurements, we collected samples from 65 lung cancer patients and 31 healthy volunteers. Lung cancer patients were in different disease stages and under treatment with different regimes. Mixed expiratory and indoor air samples were collected in Tedlar bags, and either analyzed directly by PTR-MS or transferred to glass vials and analyzed by gas chromatography mass spectrometry (GCMS). Only those measurements of compounds were considered, which showed at least a 15% higher concentration in exhaled breath than in indoor air. Compounds related to smoking behavior such as acetonitrile and benzene were not used to differentiate between lung cancer patients and healthy volunteers. Results Isoprene, acetone and methanol are compounds appearing in everybody's exhaled breath. These three main compounds of exhaled breath show slightly lower concentrations in lung cancer patients as compared to healthy volunteers (p < 0.01 for isoprene and acetone, p = 0.011 for methanol; PTR

  10. Noninvasive detection of lung cancer by analysis of exhaled breath.

    PubMed

    Bajtarevic, Amel; Ager, Clemens; Pienz, Martin; Klieber, Martin; Schwarz, Konrad; Ligor, Magdalena; Ligor, Tomasz; Filipiak, Wojciech; Denz, Hubert; Fiegl, Michael; Hilbe, Wolfgang; Weiss, Wolfgang; Lukas, Peter; Jamnig, Herbert; Hackl, Martin; Haidenberger, Alfred; Buszewski, Bogusław; Miekisch, Wolfram; Schubert, Jochen; Amann, Anton

    2009-09-29

    Lung cancer is one of the leading causes of death in Europe and the western world. At present, diagnosis of lung cancer very often happens late in the course of the disease since inexpensive, non-invasive and sufficiently sensitive and specific screening methods are not available. Even though the CT diagnostic methods are good, it must be assured that "screening benefit outweighs risk, across all individuals screened, not only those with lung cancer". An early non-invasive diagnosis of lung cancer would improve prognosis and enlarge treatment options. Analysis of exhaled breath would be an ideal diagnostic method, since it is non-invasive and totally painless. Exhaled breath and inhaled room air samples were analyzed using proton transfer reaction mass spectrometry (PTR-MS) and solid phase microextraction with subsequent gas chromatography mass spectrometry (SPME-GCMS). For the PTR-MS measurements, 220 lung cancer patients and 441 healthy volunteers were recruited. For the GCMS measurements, we collected samples from 65 lung cancer patients and 31 healthy volunteers. Lung cancer patients were in different disease stages and under treatment with different regimes. Mixed expiratory and indoor air samples were collected in Tedlar bags, and either analyzed directly by PTR-MS or transferred to glass vials and analyzed by gas chromatography mass spectrometry (GCMS). Only those measurements of compounds were considered, which showed at least a 15% higher concentration in exhaled breath than in indoor air. Compounds related to smoking behavior such as acetonitrile and benzene were not used to differentiate between lung cancer patients and healthy volunteers. Isoprene, acetone and methanol are compounds appearing in everybody's exhaled breath. These three main compounds of exhaled breath show slightly lower concentrations in lung cancer patients as compared to healthy volunteers (p < 0.01 for isoprene and acetone, p = 0.011 for methanol; PTR-MS measurements). A comparison

  11. Modeling of indoor radon concentration from radon exhalation rates of building materials and validation through measurements.

    PubMed

    Kumar, Amit; Chauhan, R P; Joshi, Manish; Sahoo, B K

    2014-01-01

    Building materials are the second major source of indoor radon after soil. The contribution of building materials towards indoor radon depends upon the radium content and exhalation rates and can be used as a primary index for radon levels in the dwellings. The radon flux data from the building materials was used for calculation of the indoor radon concentrations and doses by many researchers using one and two dimensional model suggested by various researchers. In addition to radium content, the radon wall flux from a surface strongly depends upon the radon diffusion length (L) and thickness of the wall (2d). In the present work the indoor radon concentrations from the measured radon exhalation rate of building materials calculated using different models available in literature and validation of models was made through measurement. The variation in the predicted radon flux from different models was compared with d/L value for wall and roofs of different dwellings. The results showed that the radon concentrations predicted by models agree with experimental value. The applicability of different model with d/L ratio was discussed. The work aims to select a more appropriate and general model among available models in literature for the prediction of indoor radon. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. A cross-sectional study of exhaled carbon monoxide as a biomarker of recent household air pollution exposure

    PubMed Central

    Lee, Alison; Sanchez, Tiffany R.; Shahriar, Muhammad Hasan; Eunus, Mahbubul; Perzanowski, Matthew; Graziano, Joseph

    2016-01-01

    RATIONALE Household air pollution causes 3.5 million deaths annually. Personal exposure assessments required for examining health associations are expensive and require technical expertise, limiting the quality of research in resource-poor settings. OBJECTIVES To assess the feasibility of exhaled carbon monoxide and its relationship to continuous personal carbon monoxide monitoring and markers of respiratory health in female cooks primarily cooking with biomass fuels in Araihazar, Bangladesh. METHODS & MEASURES For a 24-hour period, exhaled carboxyhemoglobin (eCOHb) % saturation was measured before and after each cooking episode while simultaneous 24-hour personal carbon monoxide monitoring was conducted. The Coburn-Forester-Kane (CFK) equation was used to convert continuous personal CO exposures to predicted COHb % saturation. Respiratory symptoms were assessed by St. George's Respiratory Questionnaire, airway inflammation measured by exhaled breath condensate pH, and lung function determined by spirometry. Spearman's correlation was used to examine the relationship between eCOHb and CKF-derived COHb, EBC pH, and lung function variables. eCOHb % saturation was dichotomized around the median and odds ratios calculated for each respiratory symptom. MAIN RESULTS Measurement of eCOHb % saturation is feasible in a resource-poor setting. eCOHb % saturation responds to cooking episodes and demonstrates consistency when measured at the same time point 24-hours later, suggesting that eCOHb may be a sensitive biomarker of recent HAP exposures. PMID:26457622

  13. A cross-sectional study of exhaled carbon monoxide as a biomarker of recent household air pollution exposure.

    PubMed

    Lee, Alison; Sanchez, Tiffany R; Shahriar, Muhammad Hasan; Eunus, Mahbubul; Perzanowski, Matthew; Graziano, Joseph

    2015-11-01

    Household air pollution causes 3.5 million deaths annually. Personal exposure assessments required for examining health associations are expensive and require technical expertize, limiting the quality of research in resource-poor settings To assess the feasibility of exhaled carbon monoxide and its relationship to continuous personal carbon monoxide monitoring and markers of respiratory health in female cooks primarily cooking with biomass fuels in Araihazar, Bangladesh METHODS AND MEASURE: For a 24-h period, exhaled carboxyhemoglobin (eCOHb) % saturation was measured before and after each cooking episode while simultaneous 24-h personal carbon monoxide monitoring was conducted. The Coburn-Forester-Kane (CFK) equation was used to convert continuous personal CO exposures to predicted COHb % saturation. Respiratory symptoms were assessed by St. George's Respiratory Questionnaire, airway inflammation measured by exhaled breath condensate pH, and lung function determined by spirometry. Spearman's correlation was used to examine the relationship between eCOHb and CKF-derived COHb, EBC pH, and lung function variables. eCOHb % saturation was dichotomized around the median and odds ratios calculated for each respiratory symptom Measurement of eCOHb % saturation is feasible in a resource-poor setting. eCOHb % saturation responds to cooking episodes and demonstrates consistency when measured at the same time point 24-h later, suggesting that eCOHb may be a sensitive biomarker of recent HAP exposures. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Relationship between exhaled nitric oxide and childhood asthma.

    PubMed

    Frank, T L; Adisesh, A; Pickering, A C; Morrison, J F; Wright, T; Francis, H; Fletcher, A; Frank, P I; Hannaford, P

    1998-10-01

    The purpose of the study was to determine if exhaled nitric oxide levels in children varied according to their asthmatic and atopic status. Exhaled nitric oxide was measured in a sample of 93 children attending the North West Lung Centre, Manchester, United Kingdom, for the clinical evaluation of a respiratory questionnaire being developed as a screening tool in general practice. The clinical assessment included full lung function, skin prick testing, and exercise challenge. Children were said to be asthmatic either by consensus decision of three independent consultant pediatricians, who reviewed all the clinical results except the nitric oxide measurements, or by positive exercise test. Atopic asthmatic children had higher geometric mean exhaled nitric oxide levels (consensus decision, 12.5 ppb [parts per billion] 95% CI, 8.3 to 18. 8; positive exercise test, 12.2 ppb 95% CI, 7.6 to 19.7) than did nonatopic asthmatic children (3.2 ppb 95% CI, 2.3 to 4.6; 3.2 ppb 95% CI, 2.0 to 5.0), atopic nonasthmatic children (3.8 ppb 95% CI, 2. 7 to 5.5; 5.7 ppb 95% CI, 4.1 to 8.0), or nonatopic nonasthmatic children (3.4 ppb 95% CI, 2.8 to 4.1; 3.5 ppb 95% CI, 3.0 to 4.1). Thus, exhaled nitric oxide was raised in atopic asthmatics but not in nonatopic asthmatics, and these nonatopic asthmatics had levels of exhaled nitric oxide similar to those of the nonasthmatics whether atopic or not.

  15. Determination of amphetamine and methylphenidate in exhaled breath of patients undergoing attention-deficit/hyperactivity disorder treatment.

    PubMed

    Beck, Olof; Stephanson, Niclas; Sandqvist, Sören; Franck, Johan

    2014-08-01

    It has been discovered recently that exogenous substances are detectable in exhaled breath after intake. Exhaled breath therefore constitutes a new possible matrix in clinical pharmacology and toxicology. The present work was aimed at exploring this possibility further by a study on patients treated for attention-deficit/hyperactivity disorder with D-amphetamine and methylphenidate. Thirteen patients (age range: 32-61 years; 5 women) were included in the study, and breath and urine samples were collected at different times in the dose interval. Analyses of breath and urine samples were done with liquid chromatography-mass spectrometry methods. Urine was examined for amphetamine, methylphenidate, and its metabolite ritalinic acid. Among the 9 patients who received D-amphetamine medication in daily doses of 20-100 mg, amphetamine was detected in all subjects in amounts ranging from 1200 to 30,800 picogram per filter. Among 8 patients receiving methylphenidate medication in daily doses of 80-400 mg, it was detected and quantified in 7 of the cases in amounts ranging from 150 to 10,400 picogram per filter and ritalinic acid was detected and quantified in 3 of the cases ranging from 35 to 360 picogram per filter. In 1 case, methylphenidate was only detectable in breath and urine, whereas ritalinic acid was quantifiable in urine, which could indicate noncompliance, with the 4 hours of dose regimen prescribed. In a number of cases, the sampling was performed 24 hours after the last dose intake. Identification of amphetamine and methylphenidate was based on correct chromatographic retention time and correct product ion ratio with detection performed in selected reaction monitoring mode. The results confirm that amphetamine is present in exhaled breath after intake and demonstrate for the first time the presence of methylphenidate and ritalinic acid after its intake. This gives further support to the potential use of exhaled breath for detecting drug intake.

  16. [Diagnostic value of exhaled nitric oxide measurement in mild asthma].

    PubMed

    Pérez Tarazona, S; Martínez Camacho, R M; Alfonso Diego, J; Escolano Serrano, S; Talens Gandía, J

    2011-11-01

    To assess the diagnostic value of fractional exhaled nitric oxide (FE(NO)) in mild asthma. Cross-sectional descriptive study in a group of patients with no history of respiratory or allergic illness (control group) and a group of patients with a history of mild asthma with no baseline treatment (asthma group), both aged 6 to 14 years. The following examinations were performed: measurement of FE(NO) using the portable NIOX MINO(®) device, allergy tests and spirometry. Repeatability of paired FE(NO) measurements was estimated with the intraclass correlation coefficient, the repeatability coefficient and the variation coefficient. The diagnostic value was assessed with the sensitivity, specificity, area under the ROC curve and positive likelihood ratio (LR+) for each cut-off point. Eighty-seven patients were included in the control group and 57 in the asthma group. The mean FE(NO) value was 12.1 ppb (SD 13.5) in the control group and 42.9 ppb (SD 24.5) in asthmatics (P<.001). The intraclass correlation coefficient was 0.98 (95% CI: 0.96-0.99) and of 0.97 (95% CI: 0.92-0.99) in controls and asthmatics, respectively. The repeatability coefficient was 5.5 in controls and 9.2 in asthmatic children, and the median variation coefficient was 8.3% and 6.1%. The optimal cut-off value for FE(NO) was 19 ppb (sensitivity and specificity were 91.4% and 87.2%, respectively). The area under the ROC curve was 0.93 (95% CI: 0.88-0.97) (P<.001) and the LR+ was 7.1. Subclinical sensitisation to pneumoallergens accounted for most false positive cases. The determination of FE(NO) with NIOX MINO(®) has an adequate repeatability, especially for healthy patients. For asthmatic patients we recommend determining the average of two measurements. The test has a high diagnostic value in mild asthma. Subclinical sensitisation to pneumoallergens can cause the FE(NO) value to rise to pathologic levels. Copyright © 2011 Asociación Española de Pediatría. Published by Elsevier Espana. All rights

  17. Atmospheric residence time of (210)Pb determined from the activity ratios with its daughter radionuclides (210)Bi and (210)Po.

    PubMed

    Semertzidou, P; Piliposian, G T; Appleby, P G

    2016-08-01

    The residence time of (210)Pb created in the atmosphere by the decay of gaseous (222)Rn is a key parameter controlling its distribution and fallout onto the landscape. These in turn are key parameters governing the use of this natural radionuclide for dating and interpreting environmental records stored in natural archives such as lake sediments. One of the principal methods for estimating the atmospheric residence time is through measurements of the activities of the daughter radionuclides (210)Bi and (210)Po, and in particular the (210)Bi/(210)Pb and (210)Po/(210)Pb activity ratios. Calculations used in early empirical studies assumed that these were governed by a simple series of equilibrium equations. This approach does however have two failings; it takes no account of the effect of global circulation on spatial variations in the activity ratios, and no allowance is made for the impact of transport processes across the tropopause. This paper presents a simple model for calculating the distributions of (210)Pb, (210)Bi and (210)Po at northern mid-latitudes (30°-65°N), a region containing almost all the available empirical data. By comparing modelled (210)Bi/(210)Pb activity ratios with empirical data a best estimate for the tropospheric residence time of around 10 days is obtained. This is significantly longer than earlier estimates of between 4 and 7 days. The process whereby (210)Pb is transported into the stratosphere when tropospheric concentrations are high and returned from it when they are low, significantly increases the effective residence time in the atmosphere as a whole. The effect of this is to significantly enhance the long range transport of (210)Pb from its source locations. The impact is illustrated by calculations showing the distribution of (210)Pb fallout versus longitude at northern mid-latitudes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Standardised exhaled breath collection for the measurement of exhaled volatile organic compounds by proton transfer reaction mass spectrometry

    PubMed Central

    2013-01-01

    Background Exhaled breath volatile organic compound (VOC) analysis for airway disease monitoring is promising. However, contrary to nitric oxide the method for exhaled breath collection has not yet been standardized and the effects of expiratory flow and breath-hold have not been sufficiently studied. These manoeuvres may also reveal the origin of exhaled compounds. Methods 15 healthy volunteers (34 ± 7 years) participated in the study. Subjects inhaled through their nose and exhaled immediately at two different flows (5 L/min and 10 L/min) into methylated polyethylene bags. In addition, the effect of a 20 s breath-hold following inhalation to total lung capacity was studied. The samples were analyzed for ethanol and acetone levels immediately using proton-transfer-reaction mass-spectrometer (PTR-MS, Logan Research, UK). Results Ethanol levels were negatively affected by expiratory flow rate (232.70 ± 33.50 ppb vs. 202.30 ± 27.28 ppb at 5 L/min and 10 L/min, respectively, p < 0.05), but remained unchanged following the breath hold (242.50 ± 34.53 vs. 237.90 ± 35.86 ppb, without and with breath hold, respectively, p = 0.11). On the contrary, acetone levels were increased following breath hold (1.50 ± 0.18 ppm) compared to the baseline levels (1.38 ± 0.15 ppm), but were not affected by expiratory flow (1.40 ± 0.14 ppm vs. 1.49 ± 0.14 ppm, 5 L/min vs. 10 L/min, respectively, p = 0.14). The diet had no significant effects on the gasses levels which showed good inter and intra session reproducibility. Conclusions Exhalation parameters such as expiratory flow and breath-hold may affect VOC levels significantly; therefore standardisation of exhaled VOC measurements is mandatory. Our preliminary results suggest a different origin in the respiratory tract for these two gasses. PMID:23837867

  19. Assessment of airway inflammation with exhaled NO measurement

    PubMed Central

    Hatziagorou, E; Tsanakas, J

    2007-01-01

    Assessing airway inflammation is important for investigating the underlying mechanisms of many lung diseases, including asthma, chronic obstructive pulmonary disease (COPD), bronchiectasis, primary ciliary dyskinesia (PCD) and cystic fibrosis. A growing interest has recently directed toward non-invasive methods for the assessment of airway inflammation. Measurement of exhaled nitric oxide in exhaled air is an exciting innovative technique that gives new insights into the pathophysiology of lung disease and asthma in particular, with many potential clinical applications. Careful standardisation of measurement techniques has facilitated the use of this new measurement in paediatric respiratory medicine. Non-invasiveness and instantaneous results potentially make it a suitable instrument for use in children starting from the age of 4, with useful applications both in asthma diagnosis and monitoring. PMID:19582178

  20. Exhaled nitric oxide in children after accidental exposure to chlorine gas.

    PubMed

    Grasemann, Hartmut; Tschiedel, Eva; Groch, Manuela; Klepper, Jörg; Ratjen, Felix

    2007-08-01

    Chronic exposure to chlorine gas has been shown to cause occupational asthma. Acute inhalation of chlorine is known to cause airway inflammation and induce airway nitric oxide formation. Exhaled nitric oxide may therefore be a marker of airway damage after chlorine gas exposure. After accidental chlorine gas exposure in a swimming pool, exhaled nitric oxide and pulmonary function were repeatedly measured in 18 children over a 1-mo period. Symptomatic children with impaired pulmonary function had higher nitric oxide levels on the day after the exposure compared to day 8 and day 28. Differences in exhaled nitric oxide were more pronounced at a higher exhalation flow compared to lower flow, suggesting peripheral rather than central airway damage. This was in accordance with the observed changes in pulmonary function. No changes in exhaled nitric oxide were seen in asymptomatic children. These data suggest that acute chlorine gas exposure results in a mild increase of exhaled nitric oxide in symptomatic children.

  1. Hydrogen cyanide in the headspace of oral fluid and in mouth-exhaled breath.

    PubMed

    Chen, W; Metsälä, M; Vaittinen, O; Halonen, L

    2014-06-01

    Mouth-exhaled hydrogen cyanide (HCN) concentrations have previously been reported to originate from the oral cavity. However, a direct correlation between the HCN concentration in oral fluid and in mouth-exhaled breath has not been explicitly shown. In this study, we set up a new methodology to simultaneously measure HCN in the headspace of oral fluid and in mouth-exhaled breath. Our results show that there is a statistically significant correlation between stimulated oral fluid HCN and mouth-exhaled HCN (rs = 0.76, p < 0.001). This confirms that oral fluid is the main contributor to mouth-exhaled HCN. Furthermore, we observe that after the application of an oral disinfectant, both the stimulated oral fluid and mouth-exhaled HCN concentrations decrease. This implies that HCN production in the oral cavity is related to the bacterial and/or enzymatic activity.

  2. Exhaled isoprene for monitoring recovery from acute hypoxic stress.

    PubMed

    Harshman, Sean William; Geier, Brian A; Qualley, Anthony; Drummond, Leslie A; Flory, Laura; Fan, Maomian; Pitsch, Rhonda; Grigsby, Claude C; Phillips, Jeffrey B; Martin, Jennifer

    2017-10-11

    Hypoxia-like incidents in-flight have increased over the past decade causing severe safety concerns across the aviation community. As a result, the need to monitor flight crews in real-time for the onset of hypoxic conditions is paramount for continued aeronautical safety. Here, hypoxic events were simulated in the laboratory via a reduced oxygen-breathing device to determine the effect of recovery gas oxygen concentration (21% and 100%) on exhaled breath volatile organic compound (VOC) composition. Data from samples collected both serially (throughout the exposure), prior to, and following exposures yielded 326 statistically significant features, 203 of which were unique. Of those, 72 features were tentatively identified while 51 were verified with authentic standards. A comparison of samples collected serially between recovery and hypoxia time points shows a statistically significant reduction in exhaled breath isoprene (2-methyl-1,3-butadiene, log2 FC -0.399, p=0.005, FDR=0.034, q=0.033), however no significant difference in isoprene abundance was observed when comparing recovery gases (21% or 100% O2, p=0.152). Furthermore, examination of pre/post exposure 1L bag breath samples illustrate an overall increase in exhaled isoprene abundance post exposure (log2 FC 0.393, p=0.005, FDR=0.094, q=0.033) but again no significant difference between recovery gas (21% and 100%, p=0.798) was observed. A statistically significant difference in trend was observed between isoprene abundance and recovery gases O2 concentration when plotted against minimum oxygen saturation (p=0.0419 100% O2, p=0.7034 21% O2). Collectively, these results suggest exhaled isoprene is dynamic in the laboratory ROBD setup and additional experimentation will be required to fully understand the dynamics of isoprene in response to acute hypoxic stress. Creative Commons Attribution license.

  3. Exhaled breath analysis: physical methods, instruments, and medical diagnostics

    NASA Astrophysics Data System (ADS)

    Vaks, V. L.; Domracheva, E. G.; Sobakinskaya, E. A.; Chernyaeva, M. B.

    2014-07-01

    This paper reviews the analysis of exhaled breath, a rapidly growing field in noninvasive medical diagnostics that lies at the intersection of physics, chemistry, and medicine. Current data are presented on gas markers in human breath and their relation to human diseases. Various physical methods for breath analysis are described. It is shown how measurement precision and data volume requirements have stimulated technological developments and identified the problems that have to be solved to put this method into clinical practice.

  4. Optimization of sampling parameters for standardized exhaled breath sampling.

    PubMed

    Doran, Sophie; Romano, Andrea; Hanna, George B

    2017-09-05

    The lack of standardization of breath sampling is a major contributing factor to the poor repeatability of results and hence represents a barrier to the adoption of breath tests in clinical practice. On-line and bag breath sampling have advantages but do not suit multicentre clinical studies whereas storage and robust transport are essential for the conduct of wide-scale studies. Several devices have been developed to control sampling parameters and to concentrate volatile organic compounds (VOCs) onto thermal desorption (TD) tubes and subsequently transport those tubes for laboratory analysis. We conducted three experiments to investigate (i) the fraction of breath sampled (whole vs. lower expiratory exhaled breath); (ii) breath sample volume (125, 250, 500 and 1000ml) and (iii) breath sample flow rate (400, 200, 100 and 50 ml/min). The target VOCs were acetone and potential volatile biomarkers for oesophago-gastric cancer belonging to the aldehyde, fatty acids and phenol chemical classes. We also examined the collection execution time and the impact of environmental contamination. The experiments showed that the use of exhaled breath-sampling devices requires the selection of optimum sampling parameters. The increase in sample volume has improved the levels of VOCs detected. However, the influence of the fraction of exhaled breath and the flow rate depends on the target VOCs measured. The concentration of potential volatile biomarkers for oesophago-gastric cancer was not significantly different between the whole and lower airway exhaled breath. While the recovery of phenols and acetone from TD tubes was lower when breath sampling was performed at a higher flow rate, other VOCs were not affected. A dedicated 'clean air supply' overcomes the contamination from ambient air, but the breath collection device itself can be a source of contaminants. In clinical studies using VOCs to diagnose gastro-oesophageal cancer, the optimum parameters are 500mls sample

  5. Characterization of exhaled nitric oxide: introducing a new reproducible method for nasal nitric oxide measurements.

    PubMed

    Palm, J P; Graf, P; Lundberg, J O; Alving, K

    2000-08-01

    Nitric oxide (NO) is present in the human nasal airways and has been suggested to originate primarily from the paranasal sinuses. The aim of this study was to establish a new and reproducible method for measurement of nasal NO. Through repeated single-breath measurements the intra- and inter-individual variations of NO levels in nasally (into a tightly fitting mask covering the nose) and orally exhaled air were determined in healthy humans. Variations due to the methods used were investigated. The contribution of oral NO to the nasal exhalations by introducing a mouthwash procedure was also studied. This study shows distinct individual values of NO in nasally and orally exhaled air of healthy humans. Some diurnal variability was also found with a rise in NO in nasally and orally exhaled air over the day, but no, or little, day-to-day variability when comparing the results from separate mornings. There was no correlation between NO levels in nasally and orally exhaled air, whereas there was a strong correlation between NO levels in air exhaled through the left and right nostril. The levels of NO in air exhaled at 0.17 L x s(-1) through either nostril separately were higher than in air exhaled at the same flow rate through both nostrils simultaneously. After the introduction of a mouthwash procedure the level of NO in orally, but not nasally exhaled air was reduced. To conclude the method using nasal exhalation into a nose mask is highly reproducible. It is also suggested that subtracting the level of NO in orally exhaled air, after mouthwash, from that in nasally exhaled air, would adequately reflect nasal NO levels.

  6. Influences of mixed expiratory sampling parameters on exhaled volatile organic compound concentrations.

    PubMed

    Thekedar, B; Oeh, U; Szymczak, W; Hoeschen, C; Paretzke, H G

    2011-03-01

    Breath gas analysis is a promising technology for medical applications. By identifying disease-specific biomarkers in the breath of patients, a non-invasive and easy method for early diagnosis or therapy monitoring can be developed. In order to achieve this goal, one essential prerequisite is the reproducibility of the method applied, i.e. the quantification of exhaled volatile organic compounds (VOCs). The variability of breath gas VOC measurements can be affected by many factors. In this respect, sampling-specific parameters like flow rate and volume of exhalation, exhalation with or without breath holding, exhalation in single or multiple breathing and volume of air inhaled before breath gas exhalation can play a vital role. These factors affecting the measurements must be controlled by optimizing the sampling procedure. For such an optimization, it is important to know how exactly the different parameters affect the exhaled VOC concentrations. Therefore, a study has been undertaken in order to identify some effects of different breath sampling-specific parameters on the exhaled VOC profile using the mixed expired breath sampling technique. It was found that parameters such as filling the sampling bag with high or low flow rate of exhalation, with multiple or single exhalations, in different volumes of exhalation, with breath holding and under different surrounding air conditions significantly affect the concentrations of the exhaled VOCs. Therefore, the specific results of this work should be taken into account before planning new breath gas studies or developing new breath gas collection systems in order to minimize the number of artefacts affecting the concentration of exhaled VOCs.

  7. Exhaled nitric oxide concentration upon acute exposure to moderate altitude.

    PubMed

    Caspersen, C; Stang, J; Thorsen, E; Stensrud, T

    2013-03-01

    The purpose of this study was to assess immediate changes in the partial pressure of nitric oxide (NO) in exhaled gas (PE NO ) in healthy trained subjects who were acutely exposed to moderate altitude. One group of nine and another group of 20 healthy subjects were exposed to an ambient pressure of 728 hPa (546 mmHg) corresponding to an altitude of 2800 m for 5 and 90 min, respectively, in an altitude chamber. PE NO was measured offline by sampling exhaled gas in tight metal foil bags at 5, 30, 60, and 90 min. A correction for increased expiratory flow rate due to gas density effects at altitude was performed (PE NO corr). PE NO was significantly decreased by 13-16%, while the fraction of NO in exhaled gas (FE NO) was increased by 16-19% compared to sea level. There was no significant change in PE NO corr after exposure to altitude for 5, 30, 60, and 90 min. We conclude that there was no change in PENO upon arrival at altitude after correcting for gas density effects on expiratory flow rate. Corrections for altitude effects must be done before comparing measurements performed at different altitudes when using measurements of FENO to monitor athletes who have asthma during training at altitude.

  8. Measuring the exhaled breath of a manikin and human subjects.

    PubMed

    Xu, C; Nielsen, P V; Gong, G; Liu, L; Jensen, R L

    2015-04-01

    Due to scarcity of accurate information and available data of actual human breathing, this investigation focuses on characterizing the breathing dynamic process based on the measurement of healthy human subjects. The similarities and differences between one breathing thermal manikin and the human subjects, including geometry and breathing functions, were thoroughly studied. As expected, actual human breathing is more complicated than that of the manikin in terms of airflow fluctuations, individual differences, and exhaled flow directions. The simplification of manikin mouth structure could result in overestimated exhaled velocity and contaminant concentration. Furthermore, actual human breathing appears to be relatively stable and reproducible for an individual person in several conditions and is also accompanied by some uncertainties simultaneously. The averaged values are used to analyze the overall characteristics of actual human breathing. There are different characteristics of the exhaled breath between male and female subjects with or without wearing a nose clip. The experimental results obtained from the measurement of human subjects may be helpful for manikin specification or validation and accuracy assessment of CFD simulations.

  9. Radon exhalation from granites used in Saudi Arabia.

    PubMed

    al-Jarallah, M

    2001-01-01

    Measurements of radon exhalation for a total of 50 selected samples of construction materials used in Saudi Arabia were taken using a radon gas analyzer. These materials included sand, aggregate, cement, gypsum, hydrated lime, ceramics and granite. It was found that the granite samples were the main source of radon emanations. A total of 32 local and imported granite samples were tested. It was found that the radon exhalation rates per unit area from these granite samples varied from not detectable to 10.6 Bq m-2 h-1 with an average of 1.3 Bq m-2 h-1. The linear correlation coefficient between emanated radon and radium content was 0.92. The normalized radon exhalation rates from 2.0 cm thick granite samples varied from not detectable to 0.068 (Bq m-2 h-1)/(Bq kg-1) with an average of 0.030 (Bq m-2 h-1)/(Bq kg-1). The average radon emanation of the granite samples was found to be 21% of the total radium concentration. Therefore, granite can be a source of indoor radon as well as external gamma-radiation from the uranium decay series.

  10. Fractional exhaled nitric oxide measurement with a handheld device.

    PubMed

    Magori, Erhard; Hiltawsky, Karsten; Fleischer, Maximilian; Simon, Elfriede; Pohle, Roland; von Sicard, Oliver; Tawil, Angelika

    2011-06-01

    A sensing system for fractional exhaled nitric oxide (FeNO) measurement is presented, which is characterized by a compact setup and a cost potential to be made available for the patient at home. The sensing is based on the work function measurement of a phthalocyanine-type sensing material, which is shown to be sufficiently sensitive for NO(2) in the ppb range. The transducer used to measure the work function is a field effect transistor with a suspended gate electrode. Selectivity is given with respect to other breath components including typically metabolic by-products. The measurement system includes breath treatments in a simple setup, which essentially are dehumidification and a quantitative conversion of NO to NO(2) with a conversion rate of approx. 95%, using a disposable oxidation catalyst. The accomplishment of the correct exhalation maneuver and feeding of the suited portion of exhaled air to the sensor is provided by breath sampling means. The sensor is not gas consuming. This allows us to fill the measurement chamber once, instead of establishing a gas flow for the measurement. This feature simplifies the device architecture. In this paper, we report on sensor characteristics, system architecture and measurement with artificial breath-gas as well as with human breath with the device.

  11. Dispersal of exhaled air and personal exposure in displacement ventilated rooms.

    PubMed

    Bjørn, E; Nielsen, P V

    2002-09-01

    The influence of the human exhalation on flow fields, contaminant distributions, and personal exposure in displacement ventilated rooms is studied together with the effects of physical movement. Experiments are conducted in full-scale test rooms with life-sized breathing thermal manikins. Numerical simulations support the experiments. Air exhaled through the mouth can lock in a thermally stratified layer, if the vertical temperature gradient in breathing zone height is sufficiently large. With exhalation through the nose, exhaled air flows to the upper part of the room. The exhalation flow from both nose and mouth is able to penetrate the breathing zone of another person standing nearby. The stratification of exhaled air breaks down if there is physical movement in the room. As movement increases, the concentration distribution in the room will move towards a fully mixed situation. The protective effect of the boundary layer flow around the body of a moving person disappears at low speed, and is reduced for a seated person placed nearby due to horizontal air movements, which can also cause rebreathing of exhaled air for the seated person. The results indicate that the effect of the exhalation flow is no acute problem in most normal ventilation applications. However, exhalation and local effects caused by movement may be worth considering if one wishes to contain contaminants in certain areas, as in the case of tobacco smoking, in hospitals and clinics, or in certain industries.

  12. Elevated levels of exhaled nitric oxide in patients with anorexia nervosa.

    PubMed

    Oświęcimska, Joanna; Ziora, Katarzyna; Ziora, Dariusz; Machura, Edyta; Smerdziński, Sebastian; Pyś-Spychała, Magdalena; Kasperski, Jacek; Zamłyński, Jacek; Kasperska-Zajac, Alicja

    2014-09-01

    Nitric oxide (NO) is involved in eating behavior and inflammatory response. Moreover, there is evidence that NO production is altered in patients with anorexia nervosa (AN). To assess whether the overproduction of NO in AN can affect NO level in exhaled air. Exhaled NO level was studied in 23 girls with AN and compared with that of healthy age- and gender-matched nonatopic controls. Exhaled NO levels were significantly higher in girls with AN compared with healthy age-matched controls. It appears that anorexia nervosa was accompanied by a higher level of exhaled NO, likely resulting from a systemic increase in NO production because of the severe catabolic state.

  13. Investigation of Exhaled Breath Samples from Patients with Alzheimer's Disease Using Gas Chromatography-Mass Spectrometry and an Exhaled Breath Sensor System.

    PubMed

    Lau, Hui-Chong; Yu, Joon-Boo; Lee, Ho-Won; Huh, Jeung-Soo; Lim, Jeong-Ok

    2017-08-03

    Exhaled breath is a body secretion, and the sampling process of this is simple and cost effective. It can be non-invasively collected for diagnostic procedures. Variations in the chemical composition of exhaled breath resulting from gaseous exchange in the extensive capillary network of the body are proposed to be associated with pathophysiological changes. In light of the foreseeable potential of exhaled breath as a diagnostic specimen, we used gas chromatography and mass spectrometry (GC-MS) to study the chemical compounds present in exhaled breath samples from patients with Alzheimer's disease (AD), Parkinson's disease (PD), and from healthy individuals as a control group. In addition, we also designed and developed a chemical-based exhaled breath sensor system to examine the distribution pattern in the patient and control groups. The results of our study showed that several chemical compounds, such as 1-phenantherol and ethyl 3-cyano-2,3-bis (2,5,-dimethyl-3-thienyl)-acrylate, had a higher percentage area in the AD group than in the PD and control groups. These results may indicate an association of these chemical components in exhaled breath with the progression of disease. In addition, in-house fabricated exhaled breath sensor systems, containing several types of gas sensors, showed significant differences in terms of the normalized response of the sensitivity characteristics between the patient and control groups. A subsequent clustering analysis was able to distinguish between the AD patients, PD patients, and healthy individuals using principal component analysis, Sammon's mapping, and a combination of both methods, in particular when using the exhaled breath sensor array system A consisting of eight sensors. With this in mind, the exhaled breath sensor system could provide alternative option for diagnosis and be applied as a useful, effective tool for the screening and diagnosis of AD in the near future.

  14. Investigation of Exhaled Breath Samples from Patients with Alzheimer’s Disease Using Gas Chromatography-Mass Spectrometry and an Exhaled Breath Sensor System

    PubMed Central

    Lau, Hui-Chong; Yu, Joon-Boo; Lee, Ho-Won; Huh, Jeung-Soo; Lim, Jeong-Ok

    2017-01-01

    Exhaled breath is a body secretion, and the sampling process of this is simple and cost effective. It can be non-invasively collected for diagnostic procedures. Variations in the chemical composition of exhaled breath resulting from gaseous exchange in the extensive capillary network of the body are proposed to be associated with pathophysiological changes. In light of the foreseeable potential of exhaled breath as a diagnostic specimen, we used gas chromatography and mass spectrometry (GC-MS) to study the chemical compounds present in exhaled breath samples from patients with Alzheimer’s disease (AD), Parkinson’s disease (PD), and from healthy individuals as a control group. In addition, we also designed and developed a chemical-based exhaled breath sensor system to examine the distribution pattern in the patient and control groups. The results of our study showed that several chemical compounds, such as 1-phenantherol and ethyl 3-cyano-2,3-bis (2,5,-dimethyl-3-thienyl)-acrylate, had a higher percentage area in the AD group than in the PD and control groups. These results may indicate an association of these chemical components in exhaled breath with the progression of disease. In addition, in-house fabricated exhaled breath sensor systems, containing several types of gas sensors, showed significant differences in terms of the normalized response of the sensitivity characteristics between the patient and control groups. A subsequent clustering analysis was able to distinguish between the AD patients, PD patients, and healthy individuals using principal component analysis, Sammon’s mapping, and a combination of both methods, in particular when using the exhaled breath sensor array system A consisting of eight sensors. With this in mind, the exhaled breath sensor system could provide alternative option for diagnosis and be applied as a useful, effective tool for the screening and diagnosis of AD in the near future. PMID:28771180

  15. Controlled low flow off line sampling of exhaled nitric oxide in children

    PubMed Central

    Jobsis, Q; Raatgeep, H; Hop, W; de Jongste, J C

    2001-01-01

    BACKGROUND—The aim of this study was to validate exhaled nitric oxide (eNO) values obtained with an alternative off line, single breath, low flow balloon sampling method against on line sampling according to ERS and ATS guidelines in children who could perform both methods.
METHODS—One hundred and twenty seven white children of median age 14.1 years, all pupils of a secondary school, participated in the study. They performed the two different sampling techniques at three different flows of 50, 100, 150 ml/s. Additional measurements were done in random subgroups to determine the influence of the dead space air on eNO values obtained off line by excluding the first 220 ml of exhaled air. All children completed a questionnaire on respiratory and allergic disorders and underwent spirometric tests.
RESULTS—The off line eNO values were significantly higher than the on line values at all flows. At 50 ml/s the geometric mean (SE) off line eNO was 18.7 (1.1) ppb and the on line eNO was 15.1 (1.1) ppb (p<0.0001). However, when dead space air was discarded, off line and on line values were similar: at 50 ml/s off line eNO was 17.7 (1.0) ppb and on line eNO 16.0 (1.2) ppb. There was a good agreement between off line eNO values without dead space air and on line eNO: for 50 ml/s the mean on/off line ratio was 0.95 (95% agreement limits 0.63 to 1.27). The off line eNO level at 50 ml/s in 80 children with negative questionnaires for asthma, rhinitis, and eczema was 13.6 (1.0) ppb compared with 33.3 (1.1) ppb in the remaining children with positive questionnaires on asthma and allergy and/or recent symptoms of cold (p<0.0001).
CONCLUSIONS—In children, off line assessment of eNO using constant low flow sampling and excluding dead space air is feasible and produces similar results as on line assessment with the same exhalation flow rate. Both sampling methods are sufficiently sensitive to differentiate between groups of otherwise healthy school children with and

  16. Increased levels of exhaled nitric oxide during nasal and oral breathing in subjects with seasonal rhinitis.

    PubMed

    Martin, U; Bryden, K; Devoy, M; Howarth, P

    1996-03-01

    Allergic rhinitis is associated with nasal mucosal inflammation. Exhaled nitric oxide may be a useful marker of inflammation and has recently been shown to be increased in patients with asthma. The purpose of this study was to determine whether exhaled levels of nitric oxide are increased with nasal breathing in patients with seasonal allergic rhinitis compared with nonatopic individuals and whether there is an increase with oral breathing consistent with lower respiratory inflammation in the absence of clinical asthma. Nitric oxide levels in exhaled air were measured by chemiluminescence in 18 nonatopic volunteers and 32 patients with seasonal rhinitis. Measurements were made with both nasal and oral exhalation and orally after 10 seconds and 60 seconds of breath-holding. The detection limit was 1 part per billion (ppb). In control subjects nasal levels of nitric oxide in exhaled air (mean +/- SD, 24.7 +/- 9.2 ppb) were higher than those after oral exhalation (11.1 +/- 2.5 ppb, p less than 0.0001). Breath-holding significantly increased levels of nitric oxide in exhaled air in a time-dependent manner. Levels of exhaled nitric oxide were significantly higher for all measurements in patients with seasonal rhinitis, with levels without breath-holding of 35.4 +/- 11.3 ppb (p less than 0.001) in nasally exhaled air and 16.3 +/- 5.9 ppb (p less than 0.001) in orally exhaled air. Nasal levels were significantly higher than oral levels in subjects with rhinitis (p less than 0.0001). The results indicate that exhaled nitric oxide may be a useful marker for nasal inflammation in patients with seasonal rhinitis and suggest that generalized airway inflammation may be present, even without clinical asthma, in such patients.

  17. Occupational dosimetric assessment (inhalation pathway) from the application of phosphogypsum in agriculture in South West Spain.

    PubMed

    Abril, J M; García-Tenorio, R; Periáñez, R; Enamorado, S M; Andreu, L; Delgado, A

    2009-01-01

    Phosphogypsum (PG) has been traditionally applied as Ca-amendment in saline marsh soils in SW Spain, where available PG has 710+/-40Bqkg(-1) of 226Ra. This work assesses the potential radiological risk for farmers through 222Rn exhalation from PG-amended soils and by inhalation of PG-dust during its application. A three-year field experiment was conducted in a commercial farm involving two treatments: control and 25tPGha(-1) with three replicates (each 0.5ha plots). The 222Rn exhalation rate was positively correlated with potential evapotranspiration, which explained 67% of the variability. Statistically significant differences between the control and PG treatments were not found for 222Rn exhalation rates, and mean values were within the lowest quartile of the typical range for 222Rn exhalation from soils. Airborne dust samples were collected during the application of PG and sugar-beet sludge amendments. The highest PG-attributable 226Ra concentration in the dust samples was 3.3x10(2)microBqm(-3), implying negligible dose increment for exposed workers.

  18. Non-alcoholic steatohepatitis: a non-invasive diagnosis by analysis of exhaled breath.

    PubMed

    Verdam, Froukje J; Dallinga, Jan W; Driessen, Ann; de Jonge, Charlotte; Moonen, Edwin J C; van Berkel, Joep B N; Luijk, Jakobus; Bouvy, Nicole D; Buurman, Wim A; Rensen, Sander S; Greve, Jan Willem M; van Schooten, Frederik Jan

    2013-03-01

    Histological evaluation of a liver biopsy is the current gold standard to diagnose non-alcoholic steatohepatitis (NASH), but the procedure to obtain biopsies is associated with morbidity and high costs. Hence, only subjects at high risk are biopsied, leading to underestimation of NASH prevalence, and undertreatment. Since analysis of volatile organic compounds in breath has been shown to accurately identify subjects with other chronic inflammatory diseases, we investigated its potential as a non-invasive tool to diagnose NASH. Wedge-shaped liver biopsies from 65 subjects (BMI 24.8-64.3 kg/m(2)) were obtained during surgery and histologically evaluated. The profile of volatile organic compounds in pre-operative breath samples was analyzed by gas chromatography-mass spectrometry and related to liver histology scores and plasma parameters of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Three exhaled compounds were sufficient to distinguish subjects with (n=39) and without NASH (n=26), with an area under the ROC curve of 0.77. The negative and positive predictive values were 82% and 81%. In contrast, elevated ALT levels or increased AST/ALT ratios both showed negative predictive values of 43%, and positive predictive values of 88% and 70%, respectively. The breath test reduced the hypothetical percentage of undiagnosed NASH patients from 67-79% to 10%, and of misdiagnosed subjects from 49-51% to 18%. Analysis of volatile organic compounds in exhaled air is a promising method to indicate NASH presence and absence. In comparison to plasma transaminase levels, the breath test significantly reduced the percentage of missed NASH patients and the number of unnecessarily biopsied subjects. Copyright © 2012 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  19. Determinants of Exhaled Breath Condensate pH in a Large Population With Asthma

    PubMed Central

    Teague, W. Gerald; Erzurum, Serpil; Fitzpatrick, Anne; Mantri, Sneha; Dweik, Raed A.; Bleecker, Eugene R.; Meyers, Deborah; Busse, William W.; Calhoun, William J.; Castro, Mario; Chung, Kian Fan; Curran-Everett, Douglas; Israel, Elliot; Jarjour, W. Nizar; Moore, Wendy; Peters, Stephen P.; Wenzel, Sally; Hunt, John F.

    2011-01-01

    Background: Exhaled breath condensate (EBC) pH is 2 log orders below normal during acute asthma exacerbations and returns to normal with antiinflammatory therapy. However, the determinants of EBC pH, particularly in stable asthma, are poorly understood. We hypothesized that patients with severe asthma would have low EBC pH and that there would be an asthma subpopulation of patients with characteristically low values. Methods: We studied the association of EBC pH with clinical characteristics in 572 stable subjects enrolled in the Severe Asthma Research Program. These included 250 subjects with severe asthma, 291 with nonsevere asthma, and 31 healthy control subjects. Results: Overall, EBC in this population of stable, treated study subjects was not lower in severe asthma (8.02; interquartile range [IQR], 7.61-8.41) or nonsevere asthma (7.90; IQR, 7.52-8.20) than in control subjects (7.9; IQR, 7.40-8.20). However, in subjects with asthma the data clustered below and above pH 6.5. Subjects in the subpopulation with pH < 6.5 had lower fraction of exhaled NO (FeNO) values (FeNO = 22.6 ± 18.1 parts per billion) than those with pH ≥ 6.5 (39.9 ± 40.2 parts per billion; P < .0001). By multiple linear regression, low EBC pH was associated with high BMI, high BAL neutrophil counts, low prebronchodilator FEV1 ratio, high allergy symptoms, race other than white, and gastroesophageal reflux symptoms. Conclusion: Asthma is a complex syndrome. Subjects who are not experiencing an exacerbation but have low EBC pH appear to be a unique subpopulation. PMID:20966042

  20. Traffic-related air pollution affects peak expiratory flow, exhaled nitric oxide, and inflammatory nasal markers.

    PubMed

    Steerenberg, P A; Nierkens, S; Fischer, P H; van Loveren, H; Opperhuizen, A; Vos, J G; van Amsterdam, J G

    2001-01-01

    The authors used a longitudinal observational design, with repeated measures, to study the association between traffic-related air pollutants (i.e., nitric oxide, nitrogen dioxide, carbon monoxide, and Black Smoke) and respiratory symptoms. Subjects (N = 82) attended an elementary school in either Utrecht (i.e., urban children) or Bilthoven (i.e., suburban children). These two geographic areas differed with respect to levels of Black Smoke (means = 53 microg/m3 and 18 microg/m3, respectively). Levels of nitric oxide, nitrogen dioxide, carbon monoxide, and Black Smoke were consistently higher in Utrecht than in Bilthoven (mean daily ratios were 8, 1.5, 1.8, and 2.7, respectively). The authors compared mean levels of short-term effects of the aforementioned air pollutants on suburban and urban children. Urban children had higher mean levels (p = .05) of interleukin-8 (32%), urea (39%), uric acid (26%), albumin (15%), and nitric oxide metabolites (21%) in nasal lavage than did suburban children. Peak expiratory flow, exhaled nitric oxide levels, and nasal markers were associated with levels of particulate matter with diameters less than or equal to 10 microm, Black Smoke, nitrogen dioxide, and nitric oxide. With respect to per-unit increases in air pollution, urban children had more increased peak expiratory flow, higher levels of exhaled nitric oxide, and more increased release of uric acid, urea, and nitric oxide metabolites than suburban children. In summary, urban children had increased levels of inflammatory nasal markers, and their responses were more pronounced than were the suburban children's responses to the same increments of air pollution.

  1. Soil gas Rn monitoring at Chã das Caldeiras prior the 2014-15 Fogo eruption, Cape Verde

    NASA Astrophysics Data System (ADS)

    Padilla, Germán; Barrancos, José; Dionis, Samara; Fernandes, Paulo; Pérez, Nemesio M.; Sagiya, Takeshi; Padrón, Eleazar; Melián, Gladys V.; Hernández, Pedro A.; Silva, Sónia; Pereira, José Manuel; Rodríguez, Fátima; Asensio-Ramos, María; Calvo, David; Semedo, Helio

    2015-04-01

    gas 222Rn activity were originated from fracturing of rock and/or from direct magma degassing. The positive temporal correlation between 222Rn/220Rn ratio and 222Rn activity supports the hypothesis that soil 222Rn activity variations acted as a long-term precursory signal of the volcanic unrest. These results show that monitoring soil gas 222Rn, together with other geochemical and geophysical data, can be a useful monitoring tool to detect early warning signals of magma pressurization.

  2. Adsorption and desorption of noble gases on activated charcoal: II. sup 222 Rn studies in a monolayer and packed bed

    SciTech Connect

    Scarpitta, S.C.; Harley, N.H. )

    1990-10-01

    The adsorptive and desorptive characteristics of canisters containing a petroleum-based charcoal were investigated under controlled conditions of temperature, relative humidity, and Rn concentration. Charcoals exposed in a monolayer and packed bed during exposure intervals of 1-7 d demonstrate that Rn adsorption and desorption are dependent on bed depth and the amount of water adsorbed. Changes in the adsorptive and desorptive properties of the charcoal occurred near the break-point where the pores became occluded by water vapor that condenses in the entrance capillaries. Radon-222 adsorption is decreased by an order of magnitude as the amount of adsorbed water exceeds the break-point of the charcoal. The reduction in pore surface due to adsorbed water results in a marked increase in the rate of Rn loss from exposed canisters, accounting for reduced adsorption. The apparent desorption time-constant for a 2-cm bed of loose Witco 6 x 10 mesh charcoal containing 0.220-0.365 kg H{sub 2}O kg-1 is typically between 2-8 h. The apparent desorption time-constant for an equivalent packed bed containing a water vapor content of 0.026-0.060 kg H{sub 2}O kg-1, which is below the break-point of the charcoal, is about 15-30 h. Conventional charcoal canisters, if exposed in the fully-opened configuration, can achieve the break-point in less than 4 d at 70% humidity. The use of a diffusion barrier would allow for longer exposure times until the break-point of the charcoal is achieved.

  3. RADIATION EXPOSURE OF THE POPULATION FROM 222Rn AND OTHER NATURAL RADIONUCLIDES AROUND MOCHOVCE NUCLEAR POWER PLANT, SLOVAKIA.

    PubMed

    Bulko, Martin; Holý, Karol; Pohronská, Žofia; Mullerová, Monika; Böhm, Radoslav; Holá, Ol'ga

    2017-09-18

    In this article, the effective dose to the population from natural sources of ionizing radiation in the vicinity of Mochovce nuclear power plant in Slovakia is presented. All major contributions to the effective dose were taken into account, including the contributions from gamma radiation of soil and rocks, cosmic radiation, and indoor and outdoor radon and thoron. On the basis of recent indoor radon measurements in Slovak cities and publicly available data about radon concentration in the soil air, a roughly linear relationship was found between these variables. Consequently, the annual effective dose from indoor radon and thoron was conservatively estimated. For the area of interest, a map of conservatively estimated potential effective doses was created. For the villages in the vicinity of Mochovce, the conservatively estimated effective dose to the population from natural sources ranged from 5.4 to 14.6 mSv, which is four orders of magnitude higher than the contribution of radioactive discharges from Mochovce nuclear power plant. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Exhaled particles as markers of small airway inflammation in subjects with asthma.

    PubMed

    Larsson, Per; Lärstad, Mona; Bake, Björn; Hammar, Oscar; Bredberg, Anna; Almstrand, Ann-Charlotte; Mirgorodskaya, Ekaterina; Olin, Anna-Carin

    2017-09-01

    Exhaled breath contains suspended particles of respiratory tract lining fluid from the small airways. The particles are formed when closed airways open during inhalation. We have developed a method called Particles in Exhaled air (PExA(®) ) to measure and sample these particles in the exhaled aerosol. Here, we use the PExA(®) method to study the effects of birch pollen exposure on the small airways of individuals with asthma and birch pollen allergy. We hypothesized that birch pollen-induced inflammation could change the concentrations of surfactant protein A and albumin in the respiratory tract lining fluid of the small airways and influence the amount of exhaled particles. The amount of exhaled particles was reduced after birch pollen exposure in subjects with asthma and birch pollen allergy, but no significant effect on the concentrations of surfactant protein A and albumin in exhaled particles was found. The reduction in the number of exhaled particles may be due to inflammation in the small airways, which would reduce their diameter and potentially reduce the number of small airways that open and close during inhalation and exhalation. © 2015 The Authors. Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd.

  5. Fractal and Chaos Analysis for Dynamics of Radon Exhalation from Uranium Mill Tailings

    NASA Astrophysics Data System (ADS)

    Li, Yongmei; Tan, Wanyu; Tan, Kaixuan; Liu, Zehua; Xie, Yanshi

    2016-08-01

    Tailings from mining and milling of uranium ores potentially are large volumes of low-level radioactive materials. A typical environmental problem associated with uranium tailings is radon exhalation, which can significantly pose risks to environment and human health. In order to reduce these risks, it is essential to study the dynamical nature and underlying mechanism of radon exhalation from uranium mill tailings. This motivates the conduction of this study, which is based on the fractal and chaotic methods (e.g. calculating the Hurst exponent, Lyapunov exponent and correlation dimension) and laboratory experiments of the radon exhalation rates. The experimental results show that the radon exhalation rate from uranium mill tailings is highly oscillated. In addition, the nonlinear analyses of the time series of radon exhalation rate demonstrate the following points: (1) the value of Hurst exponent much larger than 0.5 indicates non-random behavior of the radon time series; (2) the positive Lyapunov exponent and non-integer correlation dimension of the time series imply that the radon exhalation from uranium tailings is a chaotic dynamical process; (3) the required minimum number of variables should be five to describe the time evolution of radon exhalation. Therefore, it can be concluded that the internal factors, including heterogeneous distribution of radium, and randomness of radium decay, as well as the fractal characteristics of the tailings, can result in the chaotic evolution of radon exhalation from the tailings.

  6. Optoacoustic Determination of Carbon Dioxide Concentration in Exhaled Breath in Various Human Diseases*

    NASA Astrophysics Data System (ADS)

    Ageev, V. G.; Nikiforova, O. Yu.

    2016-11-01

    We determined the carbon dioxide concentrations in exhaled breath from healthy donors and patients with various diseases from the absorption spectra of test samples, recorded on a laser optoacoustic gas analyzer based on a CO2 laser. We observed that the carbon dioxide concentrations in exhaled breath from healthy donors is higher than in patients with various diseases.

  7. Mathematical and statistical approaches for interpreting biomarker compounds in exhaled human breath

    EPA Science Inventory

    The various instrumental techniques, human studies, and diagnostic tests that produce data from samples of exhaled breath have one thing in common: they all need to be put into a context wherein a posed question can actually be answered. Exhaled breath contains numerous compoun...

  8. Mathematical and statistical approaches for interpreting biomarker compounds in exhaled human breath

    EPA Science Inventory

    The various instrumental techniques, human studies, and diagnostic tests that produce data from samples of exhaled breath have one thing in common: they all need to be put into a context wherein a posed question can actually be answered. Exhaled breath contains numerous compoun...

  9. Daily exhaled nitric oxide measurements and asthma exacerbations in children.

    PubMed

    van der Valk, R J P; Baraldi, E; Stern, G; Frey, U; de Jongste, J C

    2012-02-01

    Fractional exhaled Nitric Oxide (FeNO) is a biomarker for eosinophilic airway inflammation and can be measured at home on a daily basis. A short-term increase in FeNO may indicate a higher risk of future asthma exacerbations. To assess changes in FeNO before and after asthma exacerbations compared to a stable control period. A post hoc analysis was performed on daily FeNO measurements over 30 weeks in children with asthma (n = 77). Moderate exacerbations were defined by an increase in symptom scores and severe exacerbations by prescription of prednisone. Individual mean and maximum FeNO, the variability of FeNO assessed by the coefficient of variation (CV), and slopes of FeNO in time were all quantified in 3-week blocks. Cross-correlation of FeNO with symptoms and autocorrelation of FeNO were assessed in relation to exacerbations and examined as predictors for exacerbations compared to reference periods using logistic regression. Fractional exhaled nitric oxide could be assessed in relation to 25 moderate and 12 severe exacerbations. The CV, slope, cross-correlation, and autocorrelation of daily FeNO increased before moderate exacerbations. Increases in slope were also randomly seen in 19% of 2-week blocks of children without exacerbations. At least 3-5 FeNO measurements in the 3 weeks before an exacerbation were needed to calculate a slope that could predict moderate exacerbations. No specific pattern of FeNO was seen before severe exacerbations. Fractional exhaled nitric oxide monitoring revealed changes in FeNO prior to moderate exacerbations. Whether this can be used to prevent loss of asthma control should be further explored. © 2011 John Wiley & Sons A/S.

  10. Ethane and n-pentane in exhaled breath are biomarkers of exposure not effect

    PubMed Central

    Gorham, Katrine A.; Sulbaek Andersen, Mads P.; Meinardi, Simone; Delfino, Ralph J.; Staimer, Norbert; Tjoa, Thomas; Rowland, F. Sherwood; Blake, Donald R.

    2013-01-01

    The relationship of exhaled ethane and n-pentane to exhaled NO, carbonylated proteins, and indoor/outdoor atmospheric pollutants were examined in order to evaluate ethane and n-pentane as potential markers of airway inflammation and/or oxidative stress. Exhaled NO and carbonylated proteins were found to have no significant associations with either ethane (p = 0.96 and p = 0.81, respectively) or n-pentane (p = 0.44 and 0.28, respectively) when outliers were included. In the case where outliers were removed n-pentane was found to be inversely associated with carbonylated proteins. Exhaled hydrocarbons adjusted for indoor hydrocarbon concentrations were instead found to be positively associated with air pollutants (NO, NO2 and CO), suggesting pollutant exposure is driving exhaled hydrocarbon concentrations. Given these find-ings, ethane and n-pentane do not appear to be markers of airway inflammation or oxidative stress. PMID:19283520

  11. Ethane and n-pentane in exhaled breath are biomarkers of exposure not effect.

    PubMed

    Gorham, Katrine A; Sulbaek Andersen, Mads P; Meinardi, Simone; Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas; Rowland, F Sherwood; Blake, Donald R

    2009-02-01

    The relationship of exhaled ethane and n-pentane to exhaled NO, carbonylated proteins, and indoor/outdoor atmospheric pollutants were examined in order to evaluate ethane and n-pentane as potential markers of airway inflammation and/or oxidative stress. Exhaled NO and carbonylated proteins were found to have no significant associations with either ethane (p = 0.96 and p = 0.81, respectively) or n-pentane (p = 0.44 and 0.28, respectively) when outliers were included. In the case where outliers were removed n-pentane was found to be inversely associated with carbonylated proteins. Exhaled hydrocarbons adjusted for indoor hydrocarbon concentrations were instead found to be positively associated with air pollutants (NO, NO(2) and CO), suggesting pollutant exposure is driving exhaled hydrocarbon concentrations. Given these findings, ethane and n-pentane do not appear to be markers of airway inflammation or oxidative stress.

  12. Nutrient routing in omnivorous animals tracked by stable carbon isotopes in tissue and exhaled breath.

    PubMed

    Voigt, Christian C; Rex, Katja; Michener, Robert H; Speakman, John R

    2008-08-01

    Omnivorous animals feed on several food items that often differ in macronutrient and isotopic composition. Macronutrients can be used for either metabolism or body tissue synthesis and, therefore, stable C isotope ratios of exhaled breath (delta(13)C(breath)) and tissue may differ. To study nutrient routing in omnivorous animals, we measured delta(13)C(breath) in 20-g Carollia perspicillata that either ate an isotopically homogeneous carbohydrate diet or an isotopically heterogeneous protein-carbohydrate mixture. The delta(13)C(breath) converged to the delta(13)C of the ingested carbohydrates irrespective of whether proteins had been added or not. On average, delta(13)C(breath) was depleted in (13)C by only ca. -2 per thousand in relation to the delta(13)C of the dietary carbohydrates and was enriched by +8.2 per thousand in relation to the dietary proteins, suggesting that C. perspicillata may have routed most ingested proteins to body synthesis and not to metabolism. We next compared the delta(13)C(breath) with that of wing tissue (delta(13)C(tissue)) in 12 free-ranging, mostly omnivorous phyllostomid bat species. We predicted that species with a more insect biased diet--as indicated by the N isotope ratio in wing membrane tissue (delta(15)N(tissue))--should have higher delta(13)C(tissue) than delta(13)C(breath) values, since we expected body tissue to stem mostly from insect proteins and exhaled CO(2) to stem from the combustion of fruit carbohydrates. Accordingly, delta(13)C(tissue) and delta(13)C(breath) should be more similar in species that feed predominantly on plant products. The species-specific differences between delta(13)C(tissue) and delta(13)C(breath) increased with increasing delta(15)N(tissue), i.e. species with a plant-dominated diet had similar delta(13)C(tissue) and delta(13)C(breath) values, whereas species feeding at a higher trophic level had higher delta(13)C(tissue) than delta(13)C(breath) values. Our study shows that delta(13)C

  13. Measuring airway exchange of endogenous acetone using a single-exhalation breathing maneuver.

    PubMed

    Anderson, Joseph C; Lamm, Wayne J E; Hlastala, Michael P

    2006-03-01

    Exhaled acetone is measured to estimate exposure or monitor diabetes and congestive heart failure. Interpreting this measurement depends critically on where acetone exchanges in the lung. Health professionals assume exhaled acetone originates from alveolar gas exchange, but experimental data and theoretical predictions suggest that acetone comes predominantly from airway gas exchange. We measured endogenous acetone in the exhaled breath to evaluate acetone exchange in the lung. The acetone concentration in the exhalate of healthy human subjects was measured dynamically with a quadrupole mass spectrometer and was plotted against exhaled volume. Each subject performed a series of breathing maneuvers in which the steady exhaled flow rate was the only variable. Acetone phase III had a positive slope (0.054+/-0.016 liter-1) that was statistically independent of flow rate. Exhaled acetone concentration was normalized by acetone concentration in the alveolar air, as estimated by isothermal rebreathing. Acetone concentration in the rebreathed breath ranged from 0.8 to 2.0 parts per million. Normalized end-exhaled acetone concentration was dependent on flow and was 0.79+/-0.04 and 0.85+/-0.04 for the slow and fast exhalation rates, respectively. A mathematical model of airway and alveolar gas exchange was used to evaluate acetone transport in the lung. By doubling the connective tissue (epithelium+mucosal tissue) thickness, this model predicted accurately (R2=0.94+/-0.05) the experimentally measured expirograms and demonstrated that most acetone exchange occurred in the airways of the lung. Therefore, assays using exhaled acetone measurements need to be reevaluated because they may underestimate blood levels.

  14. Exhaled nitric oxide in systemic sclerosis: relationships with lung involvement and pulmonary hypertension.

    PubMed

    Rolla, G; Colagrande, P; Scappaticci, E; Chiavassa, G; Dutto, L; Cannizzo, S; Bucca, C; Morello, M; Bergerone, S; Bardini, D; Zaccagna, A; Puiatti, P; Fava, C; Cortese, G

    2000-07-01

    To measure nitric oxide (NO) concentration in exhaled air of patients with systemic sclerosis (SSc) and to investigate its relationships with lung involvement, complicated or not by pulmonary hypertension (PH). Exhaled NO was measured by chemiluminescence in 47 patients with SSc (16 with PH) and in 30 controls. All the patients underwent Doppler echocardiography to assess pulmonary artery pressure (PAP), lung function tests, and thin section computed tomographic scans of the lung to quantify the extent of fibrosing alveolitis. Exhaled NO levels were higher in patients with SSc (16.6 +/- 9.1 ppb), particularly those with interstitial lung disease (ILD) (18.3 +/- 10.4 ppb), compared to controls (9.9 +/- 2.9 ppb; p < 0.0001). In patients with PH, exhaled NO was less than in patients without PH (10.7 +/- 5.9 vs 19.6 +/- 9 ppb, respectively; p < 0.001), and patients with PH without ILD had even lower exhaled NO than patients with PH and ILD (6.6 +/- 1.1 vs 12.6 +/- 6.3 ppb; p = 0.004). There was an inverse correlation between PAP and exhaled NO (r = 04).53, p = 0.004). Exhaled NO was not correlated to age, disease duration, current therapy, or form of disease (limited or diffuse). The increased concentration of exhaled NO in patients with SSc may reflect respiratory tract inflammation. The relatively low value of exhaled NO in patients with PH and the negative correlation between PAP and exhaled NO suggest the important role of NO in regulating pulmonary vascular resistance in patients with SSc.

  15. Influence of atmospheric nitric oxide concentration on the measurement of nitric oxide in exhaled air

    PubMed Central

    Corradi, M.; Pelizzoni, A.; Majori, M.; Cuomo, A.; Munari, E. d.; Pesci, A.

    1998-01-01

    BACKGROUND—Measurement of nitric oxide (NO) in exhaled air shows promise as a non-invasive method of detecting lung inflammation. However, variable concentrations of NO are measured in environmental air. The aim of this study was to verify a possible relationship between exhaled NO and atmospheric NO values during high atmospheric NO days.
METHOD—Exhaled air from 78 healthy non-smokers of mean age 35.3 years was examined for the presence of NO using a chemiluminescence NO analyser and NO levels were expressed as part per billion (ppb). The exhaled air from all the subjects was collected into a single bag and into two sequential bags. Before each test atmospheric NO was measured.
RESULTS—The mean (SE) concentration of exhaled NO collected into the single bag was 17.1 (0.6) ppb while the mean values of exhaled NO in bags 1 and 2 were 16.7 (1.3) ppb and 13.8 (1.2) ppb, respectively. The atmospheric NO concentrations registered before each test varied from 0.4 to 71 ppb. There was a significant correlation between exhaled NO in the single bag and atmospheric NO (r = 0.38,p = 0.001). The atmospheric NO concentration also correlated with exhaled NO both in bag 1 (r = 0.44, p = 0.0001) and in bag 2 (r= 0.42, p = 0.0001). These correlations disappeared with atmospheric NO concentrations lower than 35ppb.
CONCLUSIONS—These results indicate a relationship between atmospheric NO and NO levels measured in exhaled air, therefore exhaled NO should not be measured on very high atmospheric NO days.

 PMID:9828854

  16. Real-Time Quantitative Analysis of Valproic Acid in Exhaled Breath by Low Temperature Plasma Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Gong, Xiaoxia; Shi, Songyue; Gamez, Gerardo

    2017-04-01

    Real-time analysis of exhaled human breath is a rapidly growing field in analytical science and has great potential for rapid and noninvasive clinical diagnosis and drug monitoring. In the present study, an LTP-MS method was developed for real-time, in-vivo and quantitative analysis of γ-valprolactone, a metabolite of valproic acid (VPA), in exhaled breath without any sample pretreatment. In particular, the effect of working conditions and geometry of the LTP source on the ions of interest, protonated molecular ion at m/z 143 and ammonium adduct ion at m/z 160, were systematically characterized. Tandem mass spectrometry (MS/MS) with collision-induced dissociation (CID) was carried out in order to identify γ-valprolactone molecular ions ( m/z 143), and the key fragment ion ( m/z 97) was used for quantitation. In addition, the fragmentation of ammonium adduct ions to protonated molecular ions was performed in-source to improve the signal-to-noise ratio. At optimum conditions, signal reproducibility with an RSD of 8% was achieved. The concentration of γ-valprolactone in exhaled breath was determined for the first time to be 4.83 (±0.32) ng/L by using standard addition method. Also, a calibration curve was obtained with a linear range from 0.7 to 22.5 ng/L, and the limit of detection was 0.18 ng/L for γ-valprolactone in standard gas samples. Our results show that LTP-MS is a powerful analytical platform with high sensitivity for quantitative analysis of volatile organic compounds in human breath, and can have potential applications in pharmacokinetics or for patient monitoring and treatment.

  17. Study of the correlations between fractional exhaled nitric oxide in exhaled breath and atopic status, blood eosinophils, FCER2 mutation, and asthma control in Vietnamese children

    PubMed Central

    Nguyen-Thi-Bich, Hanh; Duong-Thi-Ly, Huong; Thom, Vu Thi; Pham-Thi-Hong, Nhung; Dinh, Long Doan; Le-Thi-Minh, Huong; Craig, Timothy John; Duong-Quy, Sy

    2016-01-01

    Introduction Fractional exhaled nitric oxide (FENO) is a biomarker of airway inflammation in asthma. The measurement of FENO is utilized to assist in the diagnosis and treatment of children with asthma, especially for those treated with inhaled corticosteroids. Objectives The aims of this study were to evaluate the correlations between FENO and atopic status, blood eosinophil levels, FCER2 mutation, and asthma control in Vietnamese children. Subjects and methods This was a prospective and descriptive study approved by the local Ethical Board. All children with uncontrolled asthma, seen in the National Hospital of Pediatrics (Hanoi, Vietnam), were included. Exhaled breath FENO, blood eosinophils, skin prick test, total IgE, asthma control test (ACT), and FCER2 gene polymorphism were performed at inclusion. They were followed up at 3 months to evaluate clinical status, FENO levels, and ACT. Results Forty-two children with uncontrolled asthma with a mean age of 10±3 years (6–16 years) were included. The male/female ratio was 2.5/1. The mean FENO levels were 26±25 ppb. FENO was significantly higher in patients with a positive skin prick test for respiratory allergens (P<0.05). FENO was significantly correlated with blood eosinophil levels (r=0.5217; P=0.0004). Five of the 32 subjects (15.6%) had a mutation of FCER2 gene (rs28364072 SNP). In this group, the levels of FENO were highest (37±10 ppb; P<0.05). The levels of FENO were significantly decreased after 3 months of treatment (17±8 ppb vs 26±25 ppb; P<0.05). Significant correlations between inhaled corticosteroid doses and FENO levels occurred at 1 and 3 months (r=0.415, P=0.007; r=0.396, P=0.010; respectively). There were no correlations between FENO levels, ACT, and daily use of salbutamol. After 3 months, asthma remained uncontrolled in 22.2% of children. Conclusion The measurement of FENO levels is a useful and feasible tool to predict clinical, biological, and asthma control in Vietnamese children. PMID

  18. Carbon Monoxide in Exhaled Breath Testing and Therapeutics

    PubMed Central

    Ryter, Stefan W.; Choi, Augustine M.K.

    2013-01-01

    Carbon monoxide (CO), a low molecular weight gas, is a ubiquitous environmental product of organic combustion, which is also produced endogenously in the body, as the byproduct of heme metabolism. CO binds to hemoglobin, resulting in decreased oxygen delivery to bodily tissues at toxicological concentrations. At physiological concentrations, CO may have endogenous roles as a potential signaling mediator in vascular function and cellular homeostasis. Exhaled CO (eCO), similar to exhaled nitric oxide (eNO), has been evaluated as a candidate breath biomarker of pathophysiological states, including smoking status, and inflammatory diseases of the lung and other organs. eCO values have been evaluated as potential indicators of inflammation in asthma, stable COPD and exacerbations, cystic fibrosis, lung cancer, or during surgery or critical care. The utility of eCO as a marker of inflammation, and potential diagnostic value remains incompletely characterized. Among other candidate “medicinal gases” with therapeutic potential, (e.g., NO and H2S), CO has been shown to act as an effective anti-inflammatory agent in preclinical animal models of inflammatory disease, acute lung injury, sepsis, ischemia/reperfusion injury and organ graft rejection. Current and future clinical trials will evaluate the clinical applicability of this gas as a biomarker and/or therapeutic in human disease. PMID:23446063

  19. Exhaled nitric oxide measurement in patients affected by nasal polyposis.

    PubMed

    Galli, Jacopo; Montuschi, Paolo; Passàli, Giulio Cesare; Laruffa, Marianna; Parrilla, Claudio; Paludetti, Gaetano

    2012-08-01

    Nitric oxide (NO) is produced in the respiratory tract with a major contribution coming from paranasal sinuses and the nose. The pathophysiological role of NO in the airways has been debated. The aims of this study were to measure fraction of exhaled NO (FENO), a validated marker of airway inflammation, in patients affected by nasal polyposis with and without asthma; to assess the importance of FENO measurement in detecting subclinical involvement of lower airways in patients with clinical rhinosinusal symptoms; and to clarify the impact of endoscopic surgical removal of polyps on airway inflammation. The study was conducted at the O.R.L. Clinic and Clinical Pharmacology Unit, University Hospital Agostino Gemelli, Rome, Italy. Prospective study. Concentrations of FENO were measured with the NIOX system (Aerocrine, Stockholm, Sweden) by using a single-breath online method, according to the American Thoracic Society guidelines. Compared with those in healthy subjects (15 [11-19] ppb, n = 15; P < .0001), FENO values were elevated in patients with nasal polyposis (41 [21-77] ppb, n = 43). There was no significant difference in FENO concentrations between asthmatic and nonasthmatic patients with nasal polyposis (P = .73). Concentrations of FENO in patients with nasal polyposis were decreased after surgery (64.2 [30.0-132.7] ppb vs 56.0 [26.4-73.8] ppb, respectively; P = .03). The fraction of exhaled NO is elevated in the inflammatory process involving both the rhinosinusal district and lower airways, supporting the one-airway disease hypothesis.

  20. Exhaled nitric oxide is age-dependent in asthma.

    PubMed

    Avital, Avraham; Uwyyed, Kamal; Berkman, Neville; Bar-Yishay, Ephraim; Godfrey, Simon; Springer, Chaim

    2003-11-01

    We determined whether the exhaled nitric oxide (eNO) level in asthmatics is age-dependent. Eighty-seven asthmatic patients aged 2-41 years were studied. Hyperreactivity to adenosine 5'-monophosphate (AMP) was used to confirm asthma (Exhaled NO was measured in the younger group by the tidal breathing method (TBm) and in the older subjects by the slow vital capacity method (SVCm). TBm and SVCm were compared in 21 other subjects, and there was a significant correlation between the two values (r = 0.96, P < 0.0001). The equation of correlation between the two methods was eNOTBm = 0.78eNOSVCm - 0.51. Within asthmatic patients, we found a significant increase in eNO with age (P < 0.0001), while there was no significant difference in AMP reactivity (P = 0.35). We conclude that eNO in asthmatic patients is age-dependent, with lower values in young children.

  1. Exhaled hydrogen peroxide correlates with the release of reactive oxygen species by blood phagocytes in healthy subjects.

    PubMed

    Szkudlarek, U; Maria, L; Kasielski, M; Kaucka, S; Nowak, D

    2003-06-01

    Various cells including polymorphonuclear leukocytes, alveolar macrophages and type-II pneumocytes may be a source of exhaled hydrogen peroxide (H2O2) in airways of humans. H2O2 can convert into hydroxyl radicals leading to peroxidative damage of airways structures and formation of volatile thiobarbituric acid-reactive substances (TBARs). We tested whether exhalation of H2O2 and TBARs by healthy subjects depends on reactive oxygen species generation from blood phagocytes. The expired breath condensate (EBC) and blood specimens were collected from 41 healthy, never smoked subjects (mean age 20.7 +/- 0.8 years, 18 men, 23 women) and then the EBC concentration of H2O2 and TBARs and 2 x 10(-5) M fMLP-provoked whole blood chemiluminescence response was measured. The mean concentration of H2O2 and TBARs in EBC was 0.28 +/- 0.17 and 0.04 +/- 0.13 microM with ratio of positive readings reaching 36/41 and 4/41, respectively. The chemiluminescence response to n-formyl-methionyl-leveyl-phenylalanine stimulation was obtained in all cases and the following parameters were estimated: basal chemiluminescence (bCl); peak chemiluminescence (pCl); absolute light emission (aCl); and peaktime. H2O2 levels in EBC positively correlated (Spearmann test) with bCl (r=0.41, P<0.01), pCl (r=0.47, P<0.01), aCl (r=0.49, P<0.001), peaktime (r=0.52, P<0.001) in the whole group and with bCl (r=0.56, P<0.01), pCl (r=0.67, P<0.01), aCl (r=0.66, P<0.01) in men and with aCl (r=0.41, P<0.05) and peaktime (r=0.48, P<0.05) in women. No association between exhaled TBARs and blood phagocytes activity was found. These results indicate that H2O2 exhalation in healthy never smoked subjects depends on ability of blood phagocytes to generate reactive oxygen species.

  2. Exhaled breath and fecal volatile organic biomarkers of chronic kidney disease.

    PubMed

    Meinardi, Simone; Jin, Kyu-Bok; Barletta, Barbara; Blake, Donald R; Vaziri, Nosratola D

    2013-03-01

    While much is known about the effect of chronic kidney disease (CKD) on composition of body fluids little is known regarding its impact on the gases found in exhaled breath or produced by intestinal microbiome. We have recently shown significant changes in the composition of intestinal microbiome in humans and animals with CKD. This study tested the hypothesis that uremia-induced changes in cellular metabolism and intestinal microbiome may modify the volatile organic metabolites found in the exhaled breath or generated by intestinal flora. SD rats were randomized to CKD (5/6 nephrectomy) or control (sham operation) groups. Exhaled breath was collected by enclosing each animal in a glass chamber flushed with clean air, then sealed for 45 min and the trapped air collected. Feces were collected, dissolved in pure water, incubated at 37 degrees C in glass reactors for 24 h and the trapped air collected. Collected gases were analyzed by gas chromatography. Over 50 gases were detected in the exhaled breath and 36 in cultured feces. Four gases in exhaled breath and 4 generated by cultured feces were significantly different in the two groups. The exhaled breath in CKD rats showed an early rise in isoprene and a late fall in linear aldehydes. The CKD animals' cultured feces released larger amounts of dimethyldisulfide, dimethyltrisulfide, and two thioesters. CKD significantly changes the composition of exhaled breath and gaseous products of intestinal flora. Analysis of breath and bowel gases may provide useful biomarkers for detection and progression of CKD and its complications.

  3. Application of the can technique and radon gas analyzer for radon exhalation measurements.

    PubMed

    Fazal-ur-Rehman; Al-Jarallah, M I; Musazay, M S; Abu-Jarad, F

    2003-01-01

    A passive "can technique" and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bqm(-2)h(-1) with an average of 1.35+/-1.40 Bqm(-2)h(-1). The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  4. Unsuitability of exhaled breath condensate for the detection of herpesviruses DNA in the respiratory tract.

    PubMed

    Costa, Cristina; Bucca, Caterina; Bergallo, Massimiliano; Solidoro, Paolo; Rolla, Giovanni; Cavallo, Rossana

    2011-05-01

    Exhaled breath condensate is a non-invasive method for detecting a wide number of molecules as well as genomic DNA in the airways. No study investigated the detection of viral DNA in exhaled breath condensate, while only one study excluded its usefulness for detection of influenza virus RNA. In this study, the suitability of exhaled breath condensate for detecting herpesviruses infection or reactivation in the respiratory tract of lung transplant recipients was evaluated. Twenty-four matched samples (exhaled breath condensate, bronchoalveolar lavage, whole blood, transbronchial biopsy) were evaluated for the detection of human cytomegalovirus (HCMV), human herpesvirus (HHV-6 and -7), Epstein-Barr virus (EBV) DNA by real-time PCR. Eighteen bronchoalveolar lavages (75%), six whole blood samples (25%), and two transbronchial biopsies (8.3%) were positive for at least one herpesvirus. Only one exhaled breath condensate specimen was positive for HCMV DNA (and positive also in the bronchoalveolar lavage, with low viral load in both specimens); while no other patient, irrespective of the viral load in any specimen or the presence of clinical symptoms and signs, had a positive exhaled breath condensate. These findings seem to exclude the suitability of exhaled breath condensate for non-invasive detection of viral DNA in the respiratory tract of lung transplant recipients.

  5. Exhalation behavior of four organic substrates and water absorbed by human skin.

    PubMed

    Naitoh, Ken; Inai, Yoshihito; Hirabayashi, Tadamichi; Tsuda, Takao

    2002-07-01

    The simultaneous measurement of several volatile organic compounds and water released from the human skin can be achieved successfully by using a modified gas chromatographic system. After the thumb of each subject was dipped in aqueous solution containing acetone, diethyl ether, ethanol, and toluene, it was dried in the air. Then the thumb attached to the sampling probe for measuring the released gases. It is found that 90% of all these chemical substrates were desorbed after 20 min. The initial exhalation rate factor for each chemical substrate was determined in every subject. Correlation factors of the linear relationships between the initial exhalation rate for hydrophilic substrates (acetone and ethanol) and the total amount of water (TAW) released from the skin were 0.94 and 0.92, respectively. However, the rate of hydrophobic toluene was not dependent on the TAW. Therefore, the exhalation rate of substrates is greatly influenced by both their hydrophilicity and TAW. Additionally, an interesting personal specific character among the 6 subjects was observed on plotting the exhalation rate of organic substrates and water during the elapsed time. With the released water mostly due to insensible perspiration, the exhalation rate of all simultaneous organic substrates decreased monotonically over the elapsed time. On the contrary, when subjects sweated emotionally, the exhalation rate of organic substrates showed some variation, namely a higher of exhalation rate compared to the case of mostly due to insensible perspiration. Therefore, emotionally-induced sweating can enhance the release of organic substrates.

  6. Exhaled Aerosol Pattern Discloses Lung Structural Abnormality: A Sensitivity Study Using Computational Modeling and Fractal Analysis

    PubMed Central

    Xi, Jinxiang; Si, Xiuhua A.; Kim, JongWon; Mckee, Edward; Lin, En-Bing

    2014-01-01

    Background Exhaled aerosol patterns, also called aerosol fingerprints, provide clues to the health of the lung and can be used to detect disease-modified airway structures. The key is how to decode the exhaled aerosol fingerprints and retrieve the lung structural information for a non-invasive identification of respiratory diseases. Objective and Methods In this study, a CFD-fractal analysis method was developed to quantify exhaled aerosol fingerprints and applied it to one benign and three malign conditions: a tracheal carina tumor, a bronchial tumor, and asthma. Respirations of tracer aerosols of 1 µm at a flow rate of 30 L/min were simulated, with exhaled distributions recorded at the mouth. Large eddy simulations and a Lagrangian tracking approach were used to simulate respiratory airflows and aerosol dynamics. Aerosol morphometric measures such as concentration disparity, spatial distributions, and fractal analysis were applied to distinguish various exhaled aerosol patterns. Findings Utilizing physiology-based modeling, we demonstrated substantial differences in exhaled aerosol distributions among normal and pathological airways, which were suggestive of the disease location and extent. With fractal analysis, we also demonstrated that exhaled aerosol patterns exhibited fractal behavior in both the entire image and selected regions of interest. Each exhaled aerosol fingerprint exhibited distinct pattern parameters such as spatial probability, fractal dimension, lacunarity, and multifractal spectrum. Furthermore, a correlation of the diseased location and exhaled aerosol spatial distribution was established for asthma. Conclusion Aerosol-fingerprint-based breath tests disclose clues about the site and severity of lung diseases and appear to be sensitive enough to be a practical tool for diagnosis and prognosis of respiratory diseases with structural abnormalities. PMID:25105680

  7. Production of carbon dioxide in a fattening pig house under field conditions. I. Exhalation by pigs

    NASA Astrophysics Data System (ADS)

    Ni, Ji-Qin; Hendriks, Jos; Coenegrachts, Jan; Vinckier, Christiaan

    Exhalation of carbon dioxide (CO 2) by pigs was investigated under field conditions in a mechanically ventilated commercial fattening house. The tranquil CO 2 exhalation rate (TCER) by pigs was defined and methodology was developed to study it. The experiments were conducted by moving groups of pigs in and out of one of the compartments in the house and comparing differences of measured CO 2 production rates. The measured TCERs ranged from 41.5 to 73.9 g CO 2 h -1 per pig for pigs from 32 to 105 kg. When pigs were very active, the CO 2 exhalation rate could be about 200% of the TCER but did not last for long time. A TCER mathematical model was developed based on 4 sets of experiments. It calculated the CO 2 exhalation by a pig at tranquil time as a function of its weight. Daily mean CO 2 exhalation rate (CER) by a pig was about 110% of the TCER. The TCER/CER model related the CO 2 exhalation to some aspects of pigs' behaviours and was the first reported model developed with direct measurement of CO 2 production rates. Five models of CO 2 exhalation in available literature were reviewed and the CER model was compared with them. There was a clear disparity among these models. The average CO 2 exhalation rate calculated with the "Ouwerkerk Model" was about three times as that obtained by the "Anderson Model" for pigs from 35 to 120 kg. The CER model produced the same CO 2 exhalation rate as the "Ouwerkerk Model" for a pig of 35 kg and a close rate to the "Klooster Model" for a pig of 85 kg.

  8. Determination of exhaled nitric oxide distributions in a diverse sample population using tunable diode laser absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Namjou, K.; Roller, C. B.; Reich, T. E.; Jeffers, J. D.; McMillen, G. L.; McCann, P. J.; Camp, M. A.

    2006-11-01

    A liquid-nitrogen free mid-infrared tunable diode laser absorption spectroscopy (TDLAS) system equipped with a folded-optical-path astigmatic Herriott cell was used to measure levels of exhaled nitric oxide (eNO) and exhaled carbon dioxide (eCO2) in breath. Quantification of absolute eNO concentrations was performed using NO/CO2 absorption ratios measured by the TDLAS system coupled with absolute eCO2 concentrations measured with a non-dispersive infrared sensor. This technique eliminated the need for routine calibrations using standard cylinder gases. The TDLAS system was used to measure eNO in children and adults (n=799, ages 5 to 64) over a period of more than one year as part of a field study. Volunteers for the study self-reported data including age, height, weight, and health status. The resulting data were used to assess system performance and to generate eNO and eCO2 distributions, which were found to be log-normal and Gaussian, respectively. There were statistically significant differences in mean eNO levels for males and females as well as for healthy and steroid naïve asthmatic volunteers not taking corticosteroid therapies. Ambient NO levels affected measured eNO concentrations only slightly, but this effect was not statistically significant.

  9. Quantification of Aerosol Hydrofluoroalkane HFA-134a Elimination in the Exhaled Human Breath Following Inhaled Corticosteroids Administration

    PubMed Central

    Shin, Hye-Won; Barletta, Barbara; Yoonessi, Leila; Meinardi, Simone; Leu, Szu-Yun; Radom-Aizik, Shlomit; Randhawa, Inderpal; Nussbaum, Eliezer; Blake, Donald R.; Cooper, Dan M.

    2015-01-01

    Inhaled corticosteroids (ICS) and β2-agonists are the primary pharmacotherapies of asthma management. However, suboptimal medication compliance is common in asthmatics and is associated with increased morbidity. We hypothesized that exhaled breath measurements of the aerosol used in the inhaled medications might prove useful as surrogate marker for asthma medication compliance. To explore this, ten healthy controls were recruited and randomly assigned to inhaled corticosteroids (Flovent HFA) or short acting bronchodilators (Proventil HFA). Both inhalers contain HFA-134a as aerosol propellant. Exhaled breath sampling and pulmonary function tests were performed prior to the inhaler medication dispersion, immediately after inhalation, then at 2, 4, 6, 8, 24, and 48 hours post administration. At baseline, mean (SD) levels of HFA-134a in the breath were 252 (156) pptv. Immediately after inhalation, HFA-134a breath levels increased to 300 X106 pptv and were still well above ambient levels 24 hours post administration. The calculated ratio of forced expiratory volume in 1 s over forced vital capacity (FEV1/FVC) did not change over time following inhaler administration. This study demonstrates, for the first time, that breath HFA-134a levels can be used to assess inhaler medication compliance. It may also be used to evaluate how effectively the medicine is delivered. PMID:26155923

  10. Fractional exhaled nitric oxide for the management of asthma in adults: a systematic review

    PubMed Central

    Harnan, Sue; Gomersall, Tim; Tappenden, Paul; Wong, Ruth; Pavord, Ian; Lawson, Rod; Everard, Mark L.

    2016-01-01

    The aim of this review was to evaluate the clinical effectiveness of fractional exhaled nitric oxide (FeNO) measured in a clinical setting for the management of asthma in adults. 13 electronic databases were searched and studies were selected against predefined inclusion criteria. Quality assessment was conducted using QUADAS-2. Class effect meta-analyses were performed. Six studies were included. Despite high levels of heterogeneity in multiple study characteristics, exploratory class effect meta-analyses were conducted. Four studies reported a wider definition of exacerbation rates (major or severe exacerbation) with a pooled rate ratio of 0.80 (95% CI 0.63–1.02). Two studies reported rates of severe exacerbations (requiring oral corticosteroid use) with a pooled rate ratio of 0.89 (95% CI 0.43–1.72). Inhaled corticosteroid use was reported by four studies, with a pooled standardised mean difference of −0.24 (95% CI −0.56–0.07). No statistically significant differences for health-related quality of life or asthma control were found. FeNO guided management showed no statistically significant benefit in terms of severe exacerbations or inhaled corticosteroid use, but showed a statistically significant reduction in exacerbations of any severity. However, further research is warranted to clearly define which management protocols (including cut-off points) offer best efficacy and which patient groups would benefit the most. PMID:26846832

  11. Dietary Nitrate Acutely and Markedly Increased Exhaled Nitric Oxide in a Cystic Fibrosis Case

    PubMed Central

    Kerley, Conor P.; Kilbride, Emma; Greally, Peter; Elnazir, Basil

    2016-01-01

    Airway nitric oxide (NO) is a ubiquitous signaling molecule with bronchoprotective, anti-inflammatory and anti-infective roles. Cystic fibrosis (CF) is a chronic lung condition associated with deceased exhaled NO. Strategies to increase exhaled NO in CF have yielded inconsistent results. A potential new method of increasing systemic NO involves ingestion of dietary, inorganic nitrate which is reduced to nitrite and NO. We present the case of a 12-year-old, athletic boy with CF who demonstrated acute but marked increases in exhaled NO following dietary nitrate consumption compared to placebo PMID:27630187

  12. Radium concentration and radon exhalation measurements using LR-115 type II plastic track detectors

    NASA Astrophysics Data System (ADS)

    Azam, A.; Naqvi, A. H.; Srivastava, D. S.

    1995-12-01

    The “Track-Etch” technique using LR-115 type II plastic track detectors has been employed for measuring the radium content and radon exhalation rates of different types of building materials. Among the eight materials studied it was found that fine aggregates (Badarpur) show the greatest radon exhalation, whereas portland cement produces minimum values of radon exhalation. Experimentally-measured values of the “effective radium content” (in Bq kg-1) their “mass exhalation” rates (in Bq kg-1d-1) and “surface exhalation” rates (in Bq m-2d-1 ) are reported.

  13. Microbiota in Exhaled Breath Condensate and the Lung.

    PubMed

    Glendinning, Laura; Wright, Steven; Tennant, Peter; Gill, Andrew C; Collie, David; McLachlan, Gerry

    2017-04-07

    The lung microbiota is commonly sampled using relatively invasive bronchoscopic procedures. Exhaled breath condensate (EBC) collection potentially offers a less invasive alternative for lung microbiota sampling. We compared lung microbiota samples retrieved by protected specimen brushings (PSB) and exhaled breath condensate collection. We also sought to assess whether aerosolised antibiotic treatment would influence the lung microbiota and whether EBC was sensitive enough to detect such changes.EBC was collected from 6 conscious sheep, and then from the same anaesthetised sheep during mechanical ventilation. Following the latter EBC collection, PSB samples were collected from separate sites within each sheep lung. On the subsequent day each sheep was then treated with nebulised colistimethate sodium. Two days after nebulisation, EBC and PSB samples were again collected. Bacterial DNA was quantified using 16S rRNA gene qPCR. The V2-V3 region of the 16S rRNA gene was amplified by PCR and sequenced using an Illumina Miseq. Quality control and operational taxonomic unit (OTU) clustering were performed within mothur.EBC contained significantly less bacterial DNA than PSB samples. EBC samples from anaesthetised animals clustered separately by their bacterial community compositions in comparison to PSB samples and 37 bacterial OTUs were identified which were differentially abundant between the two sample types. Despite only low concentrations of colistin being detected in bronchoalveolar lavage fluid, PSB samples were found to differ by their bacterial compositions pre and post colistimethate sodium treatment. Our findings indicate that microbiota in EBC samples and PSB samples are not equivalent.Importance Sampling of the lung microbiota usually necessitates performing bronchoscopic procedures which involve a hospital visit for human participants and the use of trained staff. The inconvenience and perceived discomfort of participating in this kind of research may deter

  14. Exhaled breath analysis: The new interface between medicine and engineering

    PubMed Central

    Mashir, Alquam; Dweik, Raed A.

    2010-01-01

    Exhaled breath testing is becoming an increasingly important non-invasive diagnostic method that can be used in the evaluation of health and disease states in the lung and beyond. Potential advantages of breath tests over other conventional medical tests include their non-invasive nature, low cost, and safety. To advance in this area further, however, there has to be a close collaboration between technical experts and engineers who have devices looking for clinical application(s), the medical experts who have the clinical problems looking for a test/biomarker that can be helpful in diagnosis or monitoring, and industry/commercial experts who can build and commercialize the final product. PMID:20948990

  15. Method for measuring the exhalation of radon from building materials

    SciTech Connect

    Ingersoll, J.G.; Stitt, B.D.; Zapalac, G.H.

    1982-02-01

    The health hazards associated with radon, a naturally occurring radioactive gas, may be significantly greater in buildings where ventilation is restricted. Since building materials such as concrete, gypsum, brick, and wood are potential sources of radon, it is important that their radon emanation rate be determined. A rapid and accurate method is presented for determining the radon emanation rate per mass from building materials by determining simply the radon exhalation rate per unit mass. A small sample of the material is sealed in a container from one to three days. The emanated radon is then collected on glass wool cooled to liquid-nitrogen temperature and subsequently transferred to a scintillation flask where the ..cap alpha..-activity is counted. The reproducibility errors of the measurements are on the order of 5%.

  16. Why inhaling salt water changes what we exhale.

    PubMed

    Watanabe, Wiwik; Thomas, Matthew; Clarke, Robert; Klibanov, Alexander M; Langer, Robert; Katstra, Jeffrey; Fuller, Gerald G; Griel, Lester C; Fiegel, Jennifer; Edwards, David

    2007-03-01

    We find that inhaling salt water diminishes subsequently exhaled biomaterial in man and animals due to reversible stabilization of the airway lining fluid (ALF)/air interface as a novel potential means for control of the spread of airborne infectious disease. The mechanism of this phenomenon relates to charge shielding of mucin or mucin-like macromolecules that consequently undergo gelation; this gelation alters the physical properties of the ALF surface and reduces its breakup. Cations in the nebulized solution and apparent surface viscoelasticity of the ALF (more than any other ALF intrinsic physical property) appear to be responsible for the reduced tendency of the ALF to disintegrate into very small droplets. We confirm these effects in vivo and show their reversibility through nebulization of saline solutions to anesthetized bull calves.

  17. Electronic Nose To Detect Patients with COPD From Exhaled Breath

    NASA Astrophysics Data System (ADS)

    Velásquez, Adriana; Durán, Cristhian M.; Gualdron, Oscar; Rodríguez, Juan C.; Manjarres, Leonardo

    2009-05-01

    To date, there is no effective tool analysis and detection of COPD syndrome, (Chronic Obstructive Pulmonary Disease) which is linked to smoking and, less frequently to toxic substances such as, the wood smoke or other particles produced by noxious gases. According to the World Health Organization (WHO) estimates of this disease show it affects more than 52 million people and kills more than 2.7 million human beings each year. In order to solve the problem, a low-cost Electronic Nose (EN) was developed at the University of Pamplona (N. S) Colombia, for this specific purpose and was applied to a sample group of patients with COPD as well as to others who were healthy. From the exhalation breath samples of these patients, the results were as expected; an appropriate classification of the patients with the disease, as well as from the healthy group was obtained.

  18. Detection of cancer through exhaled breath: a systematic review

    PubMed Central

    Krilaviciute, Agne; Heiss, Jonathan Alexander; Leja, Marcis; Kupcinskas, Juozas; Haick, Hossam; Brenner, Hermann

    2015-01-01

    Background Timely diagnosis of cancer represents a challenging task; in particular, there is a need for reliable non-invasive screening tools that could achieve high levels of adherence at virtually no risk in population-based screening. In this review, we summarize the current evidence of exhaled breath analysis for cancer detection using standard analysis techniques and electronic nose. Methods Relevant studies were identified searching Pubmed and Web of Science databases until April 30, 2015. Information on breath test performance, such as sensitivity and specificity, was extracted together with volatile compounds that were used to discriminate cancer patients from controls. Performance of different breath analysis techniques is provided for various cancers together with information on methodological issues, such as breath sampling protocol and validation of the results. Results Overall, 73 studies were included, where two-thirds of the studies were conducted on lung cancer. Good discrimination usually required a combination of multiple biomarkers, and area under the receiver operating characteristic curve or accuracy reached levels of 0.9 or higher in multiple studies. In 25% of the reported studies, classification models were built and validated on the same datasets. Huge variability was seen in different aspects among the studies. Conclusions Analyses of exhaled breath yielded promising results, although standardization of breath collection, sample storage and data handling remain critical issues. In order to foster breath analysis implementation into practice, larger studies should be implemented in true screening settings, paying particular attention to standardization in breath collection, consideration of covariates, and validation in independent population samples. PMID:26440312

  19. Exhaled Nitric Oxide in Systemic Sclerosis Lung Disease

    PubMed Central

    Kozij, Natalie K.; Silkoff, Philip E.; Thenganatt, John; Chakravorty, Shobha

    2017-01-01

    Background. Exhaled nitric oxide (eNO) is a potential biomarker to distinguish systemic sclerosis (SSc) associated pulmonary arterial hypertension (PAH) and interstitial lung disease (ILD). We evaluated the discriminative validity, feasibility, methods of eNO measurement, and magnitude of differences across lung diseases, disease-subsets (SSc, systemic lupus erythematosus), and healthy-controls. Methods. Consecutive subjects in the UHN Pulmonary Hypertension Programme were recruited. Exhaled nitric oxide was measured at 50 mL/s intervals using chemiluminescent detection. Alveolar and conducting airway NO were partitioned using a two-compartment model of axial diffusion (CMAD) and the trumpet model of axial diffusion (TMAD). Results. Sixty subjects were evaluated. Using the CMAD model, control subjects had lower median (IQR) alveolar NO than all PAH subjects (2.0 (1.5, 2.5) versus 3.14 ppb (2.3, 4.0), p = 0.008). SSc-ILD had significantly lower median conducting airway NO compared to controls (1009.5 versus 1342.1 ml⁎ppb/s, p = 0.04). SSc-PAH had increased median (IQR) alveolar NO compared to controls (3.3 (3.0, 5.7) versus 2.0 ppb (1.5, 2.5), p = 0.01). SSc-PAH conducting airway NO inversely correlated with DLCO (r −0.88 (95% CI −0.99, −0.26)). Conclusion. We have demonstrated feasibility, identified that CMAD modeling is preferred in SSc, and reported the magnitude of differences across cases and controls. Our data supports discriminative validity of eNO in SSc lung disease. PMID:28293128

  20. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    This presentation will explore historical and newly emerging methods for the collection and analysis of exhaled breath for use in environmental exposure assessment studies. We will discuss their applicability and limitations with respect to environmental research. Particular em...

  1. Standardization of exhaled breath condensate (EBC) collection using a feedback regulated breathing pattern

    EPA Science Inventory

    Collection of exhaled breath condensate (EBC) fluid by cooling of expired breath is a potentially valuable approach for the detection of biomarkers associated with disease or exposure to xenobiotics. EBC is generally collected using unregulated breathing patterns, perceived to el...

  2. Standardization of exhaled breath condensate (EBC) collection using a feedback regulated breathing pattern

    EPA Science Inventory

    Collection of exhaled breath condensate (EBC) fluid by cooling of expired breath is a potentially valuable approach for the detection of biomarkers associated with disease or exposure to xenobiotics. EBC is generally collected using unregulated breathing patterns, perceived to el...

  3. RECENT DEVELOPMENTS IN EXHALED BREATH ANALYSIS AND HUMAN EXPOSURE ASSESSMENT RESEARCH

    EPA Science Inventory

    This presentation will explore historical and newly emerging methods for the collection and analysis of exhaled breath for use in environmental exposure assessment studies. We will discuss their applicability and limitations with respect to environmental research. Particular em...

  4. Shaping exhale durations for breath CO detection for men with mild mental retardation.

    PubMed

    Rea, Jerry; Williams, Dean

    2002-01-01

    Roll, Higgins, and Badger (1996) used a carbon monoxide (CO) detector to determine whether participants smoked in a smoking-cessation study. We sought to replicate their work with adults with mild mental retardation. However, verbal instructions were inadequate to establish stable exhalations of sufficient durations for reliable and accurate CO evaluation. This report describes a shaping procedure that enabled 3 of 4 participants to achieve 20-s exhalation durations.

  5. Biological monitoring of occupational exposure to isoflurane by measurement of isoflurane exhaled breath.

    PubMed

    Prado, C; Tortosa, J A; Ibarra, I; Luna, A; Periago, J F

    1997-01-01

    The relationship between isoflurane environmental concentrations in operating rooms and the corresponding isoflurane concentration in the exhaled air of the operating personnel at the end of the exposure has been investigated. Isoflurane was retained in an adsorbent cartridge and after thermal desorption the concentration was estimated by gas chromatography. Significant correlation between environmental and exhaled air isoflurane concentrations allowed the establishment of a biological exposure index and biological exposure limits corresponding to proposed atmospheric threshold values.

  6. Detection of exhaled hydrogen sulphide gas in rats exposed to intravenous sodium sulphide

    PubMed Central

    Insko, Michael A; Deckwerth, Thomas L; Hill, Paul; Toombs, Christopher F; Szabo, Csaba

    2009-01-01

    Background and purpose: Sodium sulphide (Na2S) disassociates to sodium (Na+) hydrosulphide, anion (HS−) and hydrogen sulphide (H2S) in aqueous solutions. Here we have established and characterized a method to detect H2S gas in the exhaled breath of rats. Experimental approach: Male rats were anaesthetized with ketamine and xylazine, instrumented with intravenous (i.v.) jugular vein catheters, and a tube inserted into the trachea was connected to a pneumotach connected to a H2S gas detector. Sodium sulphide, cysteine or the natural polysulphide compound diallyl disulphide were infused intravenously while the airway was monitored for exhaled H2S real time. Key results: Exhaled sulphide concentration was calculated to be in the range of 0.4–11 ppm in response to i.v. infusion rates ranging between 0.3 and 1.1 mg·kg−1·min−1. When nitric oxide synthesis was inhibited with Nω-nitro-L-arginine methyl ester the amount of H2S exhaled during i.v. infusions of sodium sulphide was significantly increased compared with that obtained with the vehicle control. An increase in circulating nitric oxide using DETA NONOate [3,3-bis(aminoethyl)-1-hydroxy-2-oxo-1-triazene] did not alter the levels of exhaled H2S during an i.v. infusion of sodium sulphide. An i.v. bolus of L-cysteine, 1 g·kg−1, and an i.v. infusion of the garlic derived natural compound diallyl disulphide, 1.8 mg·kg−1·min−1, also caused exhalation of H2S gas. Conclusions and implications: This method has shown that significant amounts of H2S are exhaled in rats during sodium sulphide infusions, and the amount exhaled can be modulated by various pharmacological interventions. PMID:19422378

  7. Clinical Effects, Exhaled Breath Condensate pH and Exhaled Nitric Oxide in Humans After Ethyl Acrylate Exposure.

    PubMed

    Hoffmeyer, F; Bünger, J; Monsé, C; Berresheim, H; Jettkant, B; Beine, A; Brüning, T; Sucker, K

    Ethyl acrylate is an irritant known to affect the upper airways and eyes. An increase of the eye blink frequency in humans was observed during exposure to 5 ppm. Studies on the lower airways are scant and our study objective was the evaluation of pH in exhaled breath condensate (EBC-pH) and nitric oxide in exhaled breath (FeNO) as markers of inflammation. Sixteen healthy volunteers were exposed for 4 h to ethyl acrylate at a concentration of 5 ppm and to sham (0.05 ppm) in an exposure laboratory. Clinical irritation symptoms, EBC-pH (at a pCO2 of 5.33 kPa) and FeNO were assessed before and after exposure. Differences after ethyl acrylate exposure were adjusted for those after sham exposure. 5 ppm ethyl acrylate induced clinical signs of local irritation in the nose and eyes, but not in lower airways. Exposure produced a subtle, but statistically significant, decrease in breathing frequency (1 breath/min; p = 0.017) and a lower EBC-pH (by 0.045 units; p = 0.037). Concerning FeNO, we did not observe significant changes compared to sham exposure. We conclude that local effects induced by 5 ppm ethyl acrylate consist of sensory irritation of eyes and nose. In addition, acute ethyl acrylate exposure to 5 ppm resulted in a net decrease of EBC-pH. Whether that can be interpreted in terms of additional lower airway irritation or already inflammatory alterations set in needs further investigations.

  8. Experimental analysis of the air velocity and contaminant dispersion of human exhalation flows.

    PubMed

    Berlanga, F A; Olmedo, I; Ruiz de Adana, M

    2017-07-01

    Human exhalation flow is a potential source of pathogens that can constitute a cross-infection risk to people in indoor environments. Thus, it is important to investigate the characteristics of this flow, its development, area of influence, and the diffusion of the exhaled contaminants. This paper uses phase-averaged particle image velocimetry together with a tracer gas (CO2 ) to study two different exhalation flows over time: the exhalation of an average male (test M) and an average female (test F), using a life-sized thermal manikin in a supine position. The exhalation jets generated for both tests are similar in terms of symmetrical geometry, vorticity values, jet opening angles, and velocity and concentration decays. However, there is a difference in the penetration length of the two flows throughout the whole exhalation process. There is also a time difference in reaching maximum velocity between the two tests. It is also possible to see that the tracer gas dispersion depends on the momentum of the jet so the test with the highest velocity decay shows the lowest concentration decay. All these results are of interest to better understand cross-infection risk. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Quantum cascade laser-based integrated cavity output spectroscopy of exhaled nitric oxide

    NASA Astrophysics Data System (ADS)

    McCurdy, M. R.; Bakhirkin, Y. A.; Tittel, F. K.

    2006-11-01

    A nitric oxide (NO) sensor employing a thermoelectrically cooled, continuous-wave, distributed feedback quantum cascade laser operating at 5.47 μm (1828 cm-1) and off-axis integrated cavity output spectroscopy was used to measure NO concentrations in exhaled breath. A minimum measurable concentration (3σ) of 3.6 parts-per-billion by volume (ppbv) of NO with a data-acquisition time of 4 s was demonstrated. Five prepared gas mixtures and 15 exhaled breath samples were measured with both the NO sensor and for intercomparison with a chemiluminescence-based NO analyzer and were found to be in agreement within 0.6 ppbv. Exhaled NO flow-independent parameters, which may provide diagnostic and therapeutic information in respiratory diseases where single-breath measurements are equivocal, were estimated from end-tidal NO concentration measurements collected at various flow rates. The results of this work indicate that a laser-based exhaled NO sensor can be used to measure exhaled nitric oxide at a range of exhalation flow rates to determine flow-independent parameters in human clinical trials.

  10. RADIUM AND RADON EXHALATION RATE IN SOIL SAMPLES OF HASSAN DISTRICT OF SOUTH KARNATAKA, INDIA.

    PubMed

    Jagadeesha, B G; Narayana, Y

    2016-10-01

    The radon exhalation rate was measured in 32 soil samples collected from Hassan district of South Karnataka. Radon exhalation rate of soil samples was measured using can technique. The results show variation of radon exhalation rate with radium content of the soil samples. A strong correlation was observed between effective radium content and radon exhalation rate. In the present work, an attempt was made to assess the levels of radon in the environment of Hassan. Radon activities were found to vary from 2.25±0.55 to 270.85±19.16 Bq m(-3) and effective radium contents vary from 12.06±2.98 to 1449.56±102.58 mBq kg(-1) Surface exhalation rates of radon vary from 1.55±0.47 to 186.43±18.57 mBq m(-2) h(-1), and mass exhalation rates of radon vary from 0.312±0.07 to 37.46±2.65 mBq kg(-1) h(-1). © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain.

    PubMed

    López-Coto, I; Mas, J L; Vargas, A; Bolívar, J P

    2014-09-15

    Nearly 1.0 × 10(8) tonnes of phosphogypsum were accumulated during last 50 years on a 1,200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by (226)Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bqm(-2)s(-1)) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bqm(-2)s(-1)).

  12. Nasal and oral contribution to inhaled and exhaled nitric oxide: a study in tracheotomized patients.

    PubMed

    Törnberg, D C F; Marteus, H; Schedin, U; Alving, K; Lundberg, J O N; Weitzberg, E

    2002-05-01

    Nitric oxide (NO) is produced at different sites in the human airways and may have several physiological effects. Orally-produced NO seems to contribute to the levels found in exhaled air. Autoinhalation of nasal NO increases oxygenation and reduces pulmonary artery pressure in humans. The aim of this study was to measure the concentration and output of NO during nasal, oral and tracheal controlled exhalation and inhalation. Ten tracheotomized patients and seven healthy subjects were studied. The mean+/-SEM fraction of exhaled NO from the nose, mouth and trachea was 56+/-8, 14+/-4 and 6+/-1 parts per billion (ppb), respectively. During single-breath nasal, oral and tracheal inhalation the fraction of inhaled NO was 64+/-14, 11+/-3 and 4+/-1, respectively. There was a marked flow dependency on nasal NO output in the healthy subjects, which was four-fold greater at the higher flow rates, during inhalation when compared to exhalation. There is a substantial contribution of nasal and oral nitric oxide during both inhalation and exhalation. Nasal nitric oxide output is markedly higher during inhalation, reaching levels similar to those that are found to have clinical effects in the trachea. These findings have implications for the measurement of nitric oxide in exhaled air and the physiological effects of autoinhaled endogenous nitric oxide.

  13. Dopant titrating ion mobility spectrometry for trace exhaled nitric oxide detection.

    PubMed

    Peng, Liying; Hua, Lei; Li, Enyou; Wang, Weiguo; Zhou, Qinghua; Wang, Xin; Wang, Changsong; Li, Jinghua; Li, Haiyang

    2015-01-05

    Ion mobility spectrometry (IMS) is a promising non-invasive tool for the analysis of exhaled gas and exhaled nitric oxide (NO), a biomarker for diagnosis of respiratory diseases. However, the high moisture in exhaled gas always brings about extra overlapping ion peaks and results in poor identification ability. In this paper, p-benzoquinone (PBQ) was introduced into IMS to eliminate the interference of overlapping ion peaks and realize the selective identification of NO. The overlapping ions caused by moisture were titrated by PBQ and then converted to hydrated PBQ anions (C6H4[Formula: see text](H2O)n). The NO concentration could be determined by quantifying gas phase hydrated nitrite anions (N[Formula: see text](H2O)n), product ions of NO. Under optimized conditions, a limit of detection (LOD) of about 1.4 ppbv and a linear range of 10-200 ppbv were obtained for NO even in 100% relative humidity (RH) purified air. Furthermore, this established method was applied to measure hourly the exhaled NO of eight healthy volunteers, and real-time monitoring the exhaled NO of an esophageal carcinoma patient during radical surgery. These results revealed the potential of the current dopant titrating IMS method in the measurement of exhaled NO for medical disease diagnosis.

  14. Could exhaled ferritin and SOD be used as markers for lung cancer and prognosis prediction purposes?

    PubMed

    Carpagnano, Giovanna E; Lacedonia, Donato; Palladino, Grazia P; Koutelou, Anna; Martinelli, Domenico; Orlando, Silvio; Foschino-Barbaro, Maria P

    2012-05-01

    Today an increasing interest is being generated by the study of lung cancer markers in the exhaled breath condensate (EBC), precisely because this sample seems to lend itself to lung cancer early screening and follow-up. Indeed, ferritin and superoxide dismutase (SOD) have recently been recognized to play a role in lung cancerogenesis and patients' survival. The aim of this study was to evaluate the clinical value and the prognostic power of exhaled ferritin and exhaled SOD in patients with lung cancer. Forty patients with nonsmall cell lung cancer (NSCLC) and 15 controls were enrolled in the study. All subjects under study underwent EBC collection and analysis of ferritin and SOD. A total of 36 patients were either given a follow-up of at least 25.5 months or followed up until death. Exhaled ferritin and SOD resulted as being higher in NSCLC than in controls and as being influenced by the stage of cancer. A pronounced survival difference was found in the presence of exhaled ferritin 300 ng/mL and exhaled SOD > 13.5 U/μL. In conclusion, although the results need to be confirmed on a larger and homogeneous population, we hypothesized that the notion of using the measurement of ferritin and SOD in the EBC could, if deemed feasible, have clinical implications in the monitoring of lung cancer and as an outcome predictor. © 2011 The Authors. European Journal of Clinical Investigation © 2011 Stichting European Society for Clinical Investigation Journal Foundation.

  15. New method for determination of trihalomethanes in exhaled breath: applications to swimming pool and bath environments.

    PubMed

    Lourencetti, Carolina; Ballester, Clara; Fernández, Pilar; Marco, Esther; Prado, Celia; Periago, Juan F; Grimalt, Joan O

    2010-03-03

    A method for the estimation of the human intake of trihalomethanes (THMs), namely chloroform, bromodichloromethane, dibromochloromethane and bromoform, during showering and bathing is reported. The method is based on the determination of these compounds in exhaled breath that is collected by solid adsorption on Tenax using a device specifically designed for this purpose. Instrumental measurements were performed by automatic thermal desorption coupled to gas chromatography with electron capture detection. THMs in exhaled breath samples were determined during showering and swimming pool attendance. The levels of these compounds in indoor air and water were also determined as reference for interpretation of the exhaled breath results. The THM concentrations in exhaled breath of the volunteers measured before the exposure experiments showed a close correspondence with the THMs levels in indoor air where the sampler was located. Limits of detection in exhaled breath were dependent on THM analytes and experimental sites. They ranged between 170 and 710 ng m(-3) in the swimming pool studies and between 97 and 460 ng m(-3) in the showering studies. Application of this method to THMs determination during showering and swimming pool activities revealed statistically significant increases in THMs concentrations when comparing exhaled breath before and after exposure.

  16. Trichloroethene levels in human blood and exhaled breath from controlled inhalation exposure.

    PubMed Central

    Pleil, J D; Fisher, J W; Lindstrom, A B

    1998-01-01

    The organic constituents of exhaled human breath are representative of bloodborne concentrations through gas exchange in the blood/breath interface in the lungs. The presence of specific compounds can be an indicator of recent exposure or represent a biological response of the subject. For volatile organic compounds, sampling and analysis of breath is preferred to direct measurement from blood samples because breath collection is noninvasive, potentially infectious waste is avoided, the sample supply is essentially limitless, and the measurement of gas-phase analytes is much simpler in a gas matrix rather than in a complex biological tissue such as blood. However, to assess the distribution of a contaminant in the body requires a reasonable estimate of the blood level. We have investigated the use of noninvasive breath measurements as a surrogate for blood measurements for (high) occupational levels of trichloroethene in a controlled exposure experiment. Subjects were placed in an exposure chamber for 24 hr; they were exposed to 100 parts per million by volume trichloroethene for the initial 4 hr and to purified air for the remaining 20 hr. Matched breath and blood samples were collected periodically during the experiment. We modeled the resulting concentration data with respect to their time course and assessed the blood/breath relationship during the exposure (uptake) period and during the postexposure (elimination) period. Estimates for peak blood levels, compartmental distribution, and time constants were calculated from breath data and compared to direct blood measurements to assess the validity of the breath measurement methodology. Blood/breath partition coefficients were studied during both uptake and elimination. At equilibrium conditions at the end of the exposure, we could predict actual blood levels using breath elimination curve calculations and a literature value partition coefficient with a mean ratio of calculated:measured of 0.98 and standard error

  17. An estimate of hydrothermal fluid residence times and vent chimney growth rates based on 210Pb Pb ratios and mineralogic studies of sulfides dredged from the Juan de Fuca Ridge

    USGS Publications Warehouse

    Kadko, D.; Koski, R.; Tatsumoto, M.; Bouse, R.

    1985-01-01

    The 210Pb Pb ratios across two sulfide samples dredged from the Juan de Fuca Ridge are used to estimate the growth rate of the sulfide material and the residence time of the hydrothermal fluid within the oceanic crust from the onset of basalt alteration. 210Pb is added to the hydrothermal fluid by two processes: (1) high-temperature alteration of basalt and (2) if the residence time of the fluid is on the order of the 22.3-year half-life of 210Pb, by in-situ growth from 222Rn (Krishnaswami and Turekian, 1982). Stable lead is derived only from the alteration of basalt. The 210Pb Pb ratio across one sample was ??? 0.5 dpm/10-6 g Pb, and across the other it was ??? 0.4 dpm/10-6 g Pb. These values are quite close to the 238U Pb ratios of basalts from the area, suggesting that the residence time of the hydrothermal fluid from the onset of basalt alteration is appreciably less than the mean life of 210Pb, i.e., the time required for ingrowth from the radon. An apparent growth rate of 1.2 cm/yr is derived from the slope of the 210Pb Pb curve for one of the samples. This is consistent with its mineralogy and texture which suggest an accretionary pattern of development. There is no obvious sequential growth pattern, and virtually no gradient in 210Pb Pb across the second sample. This is consistent with alteration of the original 210Pb Pb distribution by extensive remobilization reactions which are inferred from the mineralogic and textural relationships of the sample. ?? 1985.

  18. Phosgene- and chlorine-induced acute lung injury in rats: comparison of cardiopulmonary function and biomarkers in exhaled breath.

    PubMed

    Luo, Sa; Trübel, Hubert; Wang, Chen; Pauluhn, Jürgen

    2014-12-04

    This study compares changes in cardiopulmonary function, selected endpoints in exhaled breath, blood, and bronchoalveolar lavage fluid (BAL) following a single, high-level 30-min nose-only exposure of rats to chlorine and phosgene gas. The time-course of lung injury was systematically examined up to 1-day post-exposure with the objective to identify early diagnostic biomarkers suitable to guide countermeasures to accidental exposures. Chlorine, due to its water solubility, penetrates the lung concentration-dependently whereas the poorly water-soluble phosgene reaches the alveolar region without any appreciable extent of airway injury. Cardiopulmonary endpoints were continually recorded by telemetry and barometric plethysmography for 20h. At several time points blood was collected to evaluate evidence of hemoconcentration, changes in hemostasis, and osteopontin. One day post-exposure, protein, osteopontin, and cytodifferentials were determined in BAL. Nitric oxide (eNO) and eCO2 were non-invasively examined in exhaled breath 5 and 24h post-exposure. Chlorine-exposed rats elaborated a reflexively-induced decreased respiratory rate and bradycardia whereas phosgene-exposed rats developed minimal changes in lung function but a similar magnitude of bradycardia. Despite similar initial changes in cardiac function, the phosgene-exposed rats showed different time-course changes of hemoconcentration and lung weights as compared to chlorine-exposed rats. eNO/eCO2 ratios were most affected in chlorine-exposed rats in the absence of any marked time-related changes. This outcome appears to demonstrate that nociceptive reflexes with changes in cardiopulmonary function resemble typical patterns of mixed airway-alveolar irritation in chlorine-exposed rats and alveolar irritation in phosgene-exposed rats. The degree and time-course of pulmonary injury was reflected best by eNO/eCO2 ratios, hemoconcentration, and protein in BAL. Increased fibrin in blood occurred only in chlorine

  19. LASER BIOLOGY AND MEDICINE: Application of tunable diode lasers for a highly sensitive analysis of gaseous biomarkers in exhaled air

    NASA Astrophysics Data System (ADS)

    Stepanov, E. V.; Milyaev, Varerii A.

    2002-11-01

    The application of tunable diode lasers for a highly sensitive analysis of gaseous biomarkers in exhaled air in biomedical diagnostics is discussed. The principle of operation and the design of a laser analyser for studying the composition of exhaled air are described. The results of detection of gaseous biomarkers in exhaled air, including clinical studies, which demonstrate the diagnostic possibilities of the method, are presented.

  20. An Acoustic-Based Method to Detect and Quantify the Effect of Exhalation into a Dry Powder Inhaler.

    PubMed

    Holmes, Martin S; Seheult, Jansen N; O'Connell, Peter; D'Arcy, Shona; Ehrhardt, Carsten; Healy, Anne Marie; Costello, Richard W; Reilly, Richard B

    2015-08-01

    Dry powder inhaler (DPI) users frequently exhale into their inhaler mouthpiece before the inhalation step. This error in technique compromises the integrity of the drug and results in poor bronchodilation. This study investigated the effect of four exhalation factors (exhalation flow rate, distance from mouth to inhaler, exhalation duration, and relative air humidity) on dry powder dose delivery. Given that acoustic energy can be related to the factors associated with exhalation sounds, we then aimed to develop a method of identifying and quantifying this critical inhaler technique error using acoustic based methods. An in vitro test rig was developed to simulate this critical error. The effect of the four factors on subsequent drug delivery were investigated using multivariate regression models. In a further study we then used an acoustic monitoring device to unobtrusively record the sounds 22 asthmatic patients made whilst using a Diskus(™) DPI. Acoustic energy was employed to automatically detect and analyze exhalation events in the audio files. All exhalation factors had a statistically significant effect on drug delivery (p<0.05); distance from the inhaler mouthpiece had the largest effect size. Humid air exhalations were found to reduce the fine particle fraction (FPF) compared to dry air. In a dataset of 110 audio files from 22 asthmatic patients, the acoustic method detected exhalations with an accuracy of 89.1%. We were able to classify exhalations occurring 5 cm or less in the direction of the inhaler mouthpiece or recording device with a sensitivity of 72.2% and specificity of 85.7%. Exhaling into a DPI has a significant detrimental effect. Acoustic based methods can be employed to objectively detect and analyze exhalations during inhaler use, thus providing a method of remotely monitoring inhaler technique and providing personalized inhaler technique feedback.

  1. [Exhaled and nasal nitric oxide in patients with Japanese cedar pollinosis and effects of nasal steroids].

    PubMed

    Miyazaki, Y

    1999-12-01

    Nitric oxide (NO) is produced by the action of NO synthase (NOS) using L-arginine as a substrate in various cells and found in air exhaled by humans. Previous studies suggest that almost all exhaled NO is derived from the upper airways and increases in patients with untreated asthma and allergic rhinitis. Exhaled NO is inhibited by treatment with inhalation of steroids that may be caused by inhibition of inducible nitric oxide synthase (iNOS). The purpose of this study is to determine whether exhaled and nasal NO increases in patients with Japanese cedar pollinosis compared with nonallergic healthy subjects, and whether it is affected by treatment with nasal steroids. Furthermore, we investigated its relation to nasal function and allergic rhinitis. 10 patients with Japanese cedar pollinosis and 5 healthy normal subjects were tested. All subjects had no history of respiratory infection for at least 2 weeks and did not smoke. Exhaled NO was collected in a sampling bag from oral and nasal breathing, and nasal NO was sampled directly from the nasal cavity. Both were measured by a chemiluminescence NO analyzer, ML9841, at a detection limit of 1 part per billion (ppb). Subjects used nasal steroids for 2 weeks and were measured similarly afterwards. NO concentrations in nasal air and air exhaled from the nose in patients with Japanese cedar pollinosis (277.9 +/- 59.5 ppb, 34.4 +/- 3.9 ppb, n = 10) were higher than the normal subjects (153.3 +/- 30.6 ppb, 19.9 +/- 3.4 ppb, n = 5) (p < 0.05). NO exhaled from the mouth was not significantly different between patients (20.5 +/- 4.9 ppb) and normal subjects (23.7 +/- 2.6 ppb). In patients with Japanese cedar pollinosis, the concentration of nasal NO and nasal exhaled NO were significantly decreased after treatment with nasal steroids (144.0 +/- 21.0 ppb, 26.1 +/- 3.0 ppb) (p < 0.01, p < 0.05), but there was no change in oral exhaled NO (17.2 +/- 3.3 ppb). In normal subjects, oral (22.5 +/- 5.3 ppb), nasal exhaled NO (19

  2. Exhaled nitric oxide in acute respiratory syncytial virus bronchiolitis.

    PubMed

    Gadish, Tal; Soferman, Ruth; Merimovitch, Tamar; Fireman, Elizabeth; Sivan, Yakov

    2010-08-01

    To investigate fractional exhaled nitric oxide (FeNO) levels in infants during acute respiratory syncytial virus (RSV) bronchiolitis and during convalescence. Prospective cohort study. Comparison of FeNO levels between infants with laboratory-confirmed acute RSV bronchiolitis and 2 control groups: healthy infants and infants with recurrent wheezing. The Department of Pediatric Emergency Medicine and the Pediatric Pulmonary Clinic of the Tel Aviv Medical Center from November 2008 to July 2009. The FeNO levels were measured at referral and at 2 visits over 4 months after convalescence. The FeNO level was measured using the multiple-breath exhalation technique. Forty-four infants with acute RSV bronchiolitis (mean [SD] age, 6.8 [7.3] months), 21 infants with recurrent wheezing (mean [SD] age, 10.8 [7.59] months), and 32 age-matched healthy controls (mean [SD] age, 6.8 [9.1] months). Follow-up data were available for 22 children (55%) for the first follow-up visit and for 11 children (25%) for the second follow-up visit. Acute RSV bronchiolitis. The FeNO levels during acute RSV bronchiolitis vs controls and FeNO levels during follow-up vs acute-stage disease. Mean FeNO levels for RSV-positive infants were significantly lower compared with healthy controls and infants with recurrent wheezing: mean (SD), 1.89 (1.76) parts per billion (ppb), 7.28 (4.96) ppb, and 4.86 (7.49) ppb, respectively (P<.001). The FeNO levels at the 2- and 4-month follow-up visits increased to 7.74 (5.13) ppb and 11.37 (6.29) ppb, respectively (P=.001). The FeNO levels are temporarily reduced during acute RSV bronchiolitis and increase during convalescence to normal levels and higher. The mechanisms for this suppression and its relation to future wheezing and asthma need to be studied.

  3. Breath carbon stable isotope ratios identify changes in energy balance and substrate utilization in humans

    USDA-ARS?s Scientific Manuscript database

    Rapid detection of shifts in substrate utilization and energy balance would provide a compelling biofeedback tool to enable individuals to lose weight. In a pilot study, we tested whether the natural abundance of exhaled carbon stable isotope ratios (breath d13C values) reflects shifts between negat...

  4. Sponge exhalent seawater contains a unique chemical profile of dissolved organic matter

    PubMed Central

    Freeman, Christopher J.; Kujawinski, Elizabeth B.

    2017-01-01

    Sponges are efficient filter feeders, removing significant portions of particulate and dissolved organic matter (POM, DOM) from the water column. While the assimilation and respiration of POM and DOM by sponges and their abundant microbial symbiont communities have received much attention, there is virtually no information on the impact of sponge holobiont metabolism on the composition of DOM at a molecular-level. We applied untargeted and targeted metabolomics techniques to characterize DOM in seawater samples prior to entering the sponge (inhalant reef water), in samples exiting the sponge (exhalent seawater), and in samples collected just outside the reef area (off reef seawater). Samples were collected from two sponge species, Ircinia campana and Spheciospongia vesparium, on a near-shore hard bottom reef in the Florida Keys. Metabolic profiles generated from untargeted metabolomics analysis indicated that many more compounds were enhanced in the exhalent samples than in the inhalant samples. Targeted metabolomics analysis revealed differences in diversity and concentration of metabolites between exhalent and off reef seawater. For example, most of the nucleosides were enriched in the exhalent seawater, while the aromatic amino acids, caffeine and the nucleoside xanthosine were elevated in the off reef water samples. Although the metabolic profile of the exhalent seawater was unique, the impact of sponge metabolism on the overall reef DOM profile was spatially limited in our study. There were also no significant differences in the metabolic profiles of exhalent water between the two sponge species, potentially indicating that there is a characteristic DOM profile in the exhalent seawater of Caribbean sponges. Additional work is needed to determine whether the impact of sponge DOM is greater in habitats with higher sponge cover and diversity. This work provides the first insight into the molecular-level impact of sponge holobiont metabolism on reef DOM and

  5. Increased exhaled nitric oxide in patients with stable chronic obstructive pulmonary disease

    PubMed Central

    Corradi, M.; Majori, M.; Cacciani, G. C.; Consigli, G. F.; de'Munari, E.; Pesci, A.

    1999-01-01

    BACKGROUND—Nitric oxide (NO) plays an important role as an inflammatory mediator in the airways. Since chronic obstructive pulmonary disease (COPD) is characterised by airway inflammation, a study was undertaken to determine NO levels in the exhaled air of patients with COPD.
METHODS—Two groups of patients with clinically stable COPD were studied, 10 current smokers and 10 ex-smokers. Two control groups of healthy subjects consisting of 10 current smokers and 20 non-smokers were also studied. Exhaled NO levels were measured by the collection bag technique and NO chemiluminescence analyser.
RESULTS—Mean (SE) levels of exhaled NO in ex-smokers and current smokers with COPD (25.7 (3.0) ppb and 10.2 (1.4) ppb, respectively) were significantly higher than in non-smoker and current smoker control subjects (9.4 (0.8) ppb and 4.6 (0.4) ppb, respectively). In current smokers with COPD exhaled levels of NO were significantly lower than in ex-smokers. In this latter group of patients there was a significant negative correlation between smoking history (pack years) and levels of exhaled NO (r = -0.8, p = 0.002). A positive correlation was seen between forced expiratory volume in one second (FEV1) and levels of exhaled NO (r = 0.65, p = 0.001) in patients with COPD.
CONCLUSIONS—These data show that exhaled NO is increased in patients with stable COPD, both current and ex-smokers, compared with healthy control subjects.

 PMID:10377199

  6. Exhaled Aerosol Transmission of Pandemic and Seasonal H1N1 Influenza Viruses in the Ferret

    PubMed Central

    Koster, Frederick; Gouveia, Kristine; Zhou, Yue; Lowery, Kristin; Russell, Robert; MacInnes, Heather; Pollock, Zemmie; Layton, R. Colby; Cromwell, Jennifer; Toleno, Denise; Pyle, John; Zubelewicz, Michael; Harrod, Kevin; Sampath, Rangarajan; Hofstadler, Steven; Gao, Peng; Liu, Yushi; Cheng, Yung-Sung

    2012-01-01

    Person-to-person transmission of influenza viruses occurs by contact (direct and fomites) and non-contact (droplet and small particle aerosol) routes, but the quantitative dynamics and relative contributions of these routes are incompletely understood. The transmissibility of influenza strains estimated from secondary attack rates in closed human populations is confounded by large variations in population susceptibilities. An experimental method to phenotype strains for transmissibility in an animal model could provide relative efficiencies of transmission. We developed an experimental method to detect exhaled viral aerosol transmission between unanesthetized infected and susceptible ferrets, measured aerosol particle size and number, and quantified the viral genomic RNA in the exhaled aerosol. During brief 3-hour exposures to exhaled viral aerosols in airflow-controlled chambers, three strains of pandemic 2009 H1N1 strains were frequently transmitted to susceptible ferrets. In contrast one seasonal H1N1 strain was not transmitted in spite of higher levels of viral RNA in the exhaled aerosol. Among three pandemic strains, the two strains causing weight loss and illness in the intranasally infected ‘donor’ ferrets were transmitted less efficiently from the donor than the strain causing no detectable illness, suggesting that the mucosal inflammatory response may attenuate viable exhaled virus. Although exhaled viral RNA remained constant, transmission efficiency diminished from day 1 to day 5 after donor infection. Thus, aerosol transmission between ferrets may be dependent on at least four characteristics of virus-host relationships including the level of exhaled virus, infectious particle size, mucosal inflammation, and viral replication efficiency in susceptible mucosa. PMID:22509254

  7. Exhaled breath condensate – from an analytical point of view

    PubMed Central

    Dodig, Slavica; Čepelak, Ivana

    2013-01-01

    Over the past three decades, the goal of many researchers is analysis of exhaled breath condensate (EBC) as noninvasively obtained sample. A total quality in laboratory diagnostic processes in EBC analysis was investigated: pre-analytical (formation, collection, storage of EBC), analytical (sensitivity of applied methods, standardization) and post-analytical (interpretation of results) phases. EBC analysis is still used as a research tool. Limitations referred to pre-analytical, analytical, and post-analytical phases of EBC analysis are numerous, e.g. low concentrations of EBC constituents, single-analyte methods lack in sensitivity, and multi-analyte has not been fully explored, and reference values are not established. When all, pre-analytical, analytical and post-analytical requirements are met, EBC biomarkers as well as biomarker patterns can be selected and EBC analysis can hopefully be used in clinical practice, in both, the diagnosis and in the longitudinal follow-up of patients, resulting in better outcome of disease. PMID:24266297

  8. Exhaled nitric oxide levels in children with chronic adenotonsillar disease.

    PubMed

    Torretta, S; Marchisio, P; Esposito, S; Garavello, W; Cappadona, M; Clemente, I A; Pignataro, L

    2011-01-01

    Exhaled nitric oxide (eNO) is a highly reactive biological mediator that has recently been associated with chronic tonsillar disease in adults, but there are no published data concerning eNO levels in their pediatric counterparts. The aim of this study is to measure mean eNO levels in children with chronic adenotonsillitis or adenotonsillar hypertrophy, and assess the effects of potential confounding factors. Children aged 3-17 years were divided into three groups (chronic adenotonsillitis, adenotonsillar hypertrophy and controls). Their eNO levels were measured in accordance with the international guidelines, and their other clinical and anamnestic characteristics were recorded. The mean eNO level in the children with chronic adenotonsillitis was slightly higher than that in the other groups, but there was no statistically significant between-group difference. Age (p=0.009), allergy (p=0.05) and body mass index (p=0.03), but not the mean grade of adenoidal or tonsil hypertrophy, were all statistically related to mean eNO levels. These preliminary results indicate the lack of an increase in mean eNO levels in children with chronic adenotonsillar disease, with no substantial difference between children with chronic adenotonsillitis and those with adenotonsillar hypertrophy.

  9. Sedimentary exhalative (sedex) zinc-lead-silver deposit model

    USGS Publications Warehouse

    Emsbo, Poul; Seal, Robert R.; Breit, George N.; Diehl, Sharon F.; Shah, Anjana K.

    2016-10-28

    This report draws on previous syntheses and basic research studies of sedimentary exhalative (sedex) deposits to arrive at the defining criteria, both descriptive and genetic, for sedex-type deposits. Studies of the tectonic, sedimentary, and fluid evolution of modern and ancient sedimentary basins have also been used to select defining criteria. The focus here is on the geologic characteristics of sedex deposit-hosting basins that contain greater than 10 million metric tons of zinc and lead. The enormous size of sedex deposits strongly suggests that basin-scale geologic processes are involved in their formation. It follows that mass balance constraints of basinal processes can provide a conceptual underpinning for the evaluation of potential ore-forming mechanisms and the identification of geologic indicators for ore potential in specific sedimentary basins. Empirical data and a genetic understanding of the physicochemical, geologic, and mass balance conditions required for each of these elements are used to establish a hierarchy of quantifiable geologic criteria that can be used in U.S. Geological Survey national assessments.  In addition, this report also provides a comprehensive evaluation of environmental considerations associated with the mining of sedex deposits.

  10. Exhaled nitric oxide in childhood asthma: a review.

    PubMed

    Pijnenburg, M W H; De Jongste, J C

    2008-02-01

    As an 'inflammometer', the fraction of nitric oxide in exhaled air (Fe(NO)) is increasingly used in the management of paediatric asthma. Fe(NO) provides us with valuable, additional information regarding the nature of underlying airway inflammation, and complements lung function testing and measurement of airway hyper-reactivity. This review focuses on clinical applications of Fe(NO) in paediatric asthma. First, Fe(NO) provides us with a practical tool to aid in the diagnosis of asthma and distinguish patients who will benefit from inhaled corticosteroids from those who will not. Second, Fe(NO) is helpful in predicting exacerbations, and predicting successful steroid reduction or withdrawal. In atopic asthmatic children Fe(NO) is beneficial in adjusting steroid doses, discerning those patients who require additional therapy from those whose medication dose could feasibly be reduced. In pre-school children Fe(NO) may be of help in the differential diagnosis of respiratory symptoms, and may potentially allow for better targeting and monitoring of anti-inflammatory treatment.

  11. Increased metal concentrations in exhaled breath condensate of industrial welders.

    PubMed

    Hoffmeyer, Frank; Weiss, Tobias; Lehnert, Martin; Pesch, Beate; Berresheim, Hans; Henry, Jana; Raulf-Heimsoth, Monika; Broding, Horst Christoph; Bünger, Jürgen; Harth, Volker; Brüning, Thomas

    2011-01-01

    It was the aim of this study to evaluate the effect of different devices on the metal concentration in exhaled breath condensate (EBC) and to prove whether working conditions in different welding companies result in diverse composition of metallic elements. The influence of two collection devices (ECoScreen, ECoScreen2) on detection of metallic elements in EBC was evaluated in 24 control subjects. Properties of ECoScreen and a frequent use can alter EBC metal content due to contamination from metallic components. ECoScreen2 turned out to be favourable for metal assessment. Concentrations of iron, nickel and chromium in EBC sampled with ECoScreen2 were compared between non-exposed controls and industrial welders. Metal concentrations in EBC were higher in 36 welders recruited from three companies. Exposure to welding fumes could be demonstrated predominantly for increased iron concentrations. Concentrations of iron and nickel differed by working conditions, but chromium could not be detected in EBC.

  12. Detection of pulmonary amylase activity in exhaled breath condensate.

    PubMed

    Zweifel, M; Rechsteiner, T; Hofer, M; Boehler, A

    2013-12-01

    Amylase activity in exhaled breath condensate (EBC) is usually interpreted as an indication of oropharyngeal contamination despite the fact that amylase can be found in pulmonary excretions. The aim of this study was to recruit and refine an amylase assay in order to detect amylase activity in any EBC sample and to develop a method to identify EBC samples containing amylase of pulmonary origin. EBC was collected from 40 volunteers with an EcoScreen condenser. Amylase assays and methods to discriminate between oropharyngeal and pulmonary proteins were tested and developed using matched EBC and saliva samples. Our refined 2-chloro-4-nitrophenyl-α-D-maltotriosid (CNP-G3) assay was 40-fold more sensitive than the most sensitive commercial assay and allowed detection of amylase activity in 30 µl of EBC. We developed a dot-blot assay which allowed detection of salivary protein in saliva diluted up to 150 000-fold. By plotting amylase activity against staining intensity we identified a few EBC samples with high amylase activity which were aligned with diluted saliva. We believe that EBC samples aligned with diluted saliva contain amylase activity introduced during EBC collection and that all other EBC samples contain amylase activity of pulmonary origin and are basically free of oropharyngeal protein contamination.

  13. Exhaled nitric oxide in patients with sleep apnea.

    PubMed

    Agustí, A G; Barbé, F; Togores, B

    1999-03-15

    Cardiovascular diseases are frequent in patients with obstructive sleep apnea syndrome (OSAS), but the mechanisms underlying this association are largely unknown. Nitric oxide (NO) is a key regulatory element of vascular physiology. The concentration of NO in the exhaled air ([NOexh]) appears to be reduced in patients with systemic and pulmonary hypertension. This study sought to investigate whether [NOexh] is abnormal in patients with OSAS, and to explore potential relationships between [NOexh] and the severity of OSAS. We measured [NOexh] in 24 patients with OSAS (apnea-hypopnea index (AHI), 55 +/- 4 hour-1) (x +/- SEM), and in 7 healthy volunteers in whom OSAS was excluded clinically. [NOexh] was measured on line by a chemiluminescence analyzer (Dasibi Environmental Corporation, Glendale, Calif). Seven patients with OSAS (29%) had a positive history of cardiovascular disease. Mean [NOexh] was 19.7 +/- 3.2 ppb in healthy subjects, and 22.2 +/- 3.0 ppb in patients with OSAS (p = ns). [Noexh] was not significantly different in those patients with or without cardiovascular disease. [NOexh] was not significantly related to the AHI, the body mass index, or the arterial O2 saturation at night. These results show that [NOexh] is not abnormal in patients with OSAS, and that it does not relate to the presence of cardiovascular disease or to any of various common indices of disease severity.

  14. Leukotrienes in exhaled breath condensate and fractional exhaled nitric oxide in workers exposed to TiO2 nanoparticles.

    PubMed

    Pelclova, Daniela; Zdimal, Vladimir; Kacer, Petr; Fenclova, Zdenka; Vlckova, Stepanka; Komarc, Martin; Navratil, Tomas; Schwarz, Jaroslav; Zikova, Nadezda; Makes, Otakar; Syslova, Kamila; Belacek, Jaroslav; Zakharov, Sergey

    2016-06-30

    Human health data regarding exposure to nanoparticles are extremely scarce and biomonitoring of exposure is lacking in spite of rodent pathological experimental data. Potential markers of the health-effects of engineered nanoparticles were examined in 30 workers exposed to TiO2 aerosol, 22 office employees of the same plant, and 45 unexposed controls. Leukotrienes (LT) B4, C4, E4, and D4 were analysed in the exhaled breath condensate (EBC) and urine via liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Fractional exhaled nitric oxide (FeNO) and spirometry was also measured. The median particle number concentration of the aerosol in the production ranged from 1.98  ×  10(4) to 2.32  ×  10(4) particles cm(-3); about 80% of the particles were  <100 nm in diameter. Median total mass concentration varied between 0.4 and 0.65 mg m(-3). All LT levels in workers' EBC were elevated relative to the controls (p  <  0.01). LTs in the EBC sample were correlated with titanium levels. Urinary LTs were not elevated in the workers and office employees. Office workers had higher LTB4 in EBC (p  <  0.05), and higher levels of FeNO (p  <  0.01). FeNO was higher in office employees with allergic diseases and was negatively correlated with smoking (p  <  0.01). In spirometry significant impairment in the workers was seen only for %VCIN and %PEF (both p  <  0.01). Multiple regression analysis confirmed a significant association between production of TiO2 and all cysteinyl LTs in EBC (p  <  0.01) and impaired %VCIN and %PEF (both p  <  0.01). LTB4 was also associated with smoking (p  <  0.01). LT levels complemented our earlier findings of DNA, protein, and lipid damage in the EBC of workers with nanoTiO2 exposures. Cysteinyl LTs in EBC analysis suggest inflammation and potential fibrotic changes in the lungs; they may be helpful for monitoring the biological

  15. Radon emanation coefficients for phosphogypsum.

    PubMed

    Rutherford, P M; Dudas, M J; Arocena, J M

    1995-10-01

    Phosphogypsum is a by-product of the phosphate fertilizer industry which is stockpiled in large quantities world-wide. Phosphogypsum consists mainly of dihydrate gypsum (CaSO42H2O) but also contains elevated concentrations of 226Ra and other inorganic species which originate from the processing of phosphate rock. 222Rn gas is the first decay product of 226Ra and has been identified as one of the major environmental concerns associated with phosphogypsum. This study was conducted to determine effects of particle size, weathering, and moisture content on the 222Rn emanation coefficient (epsilon) for phosphogypsum. Average epsilon for air-dry, unfractionated phosphogypsums derived from Togo, Florida, or Idaho rock was approximately 12%. Average epsilon for fine fraction phosphogypsum (< 20 microns diameter) was greater than for unfractionated phosphogypsum by a factor of 4.6, 1.4, and 4.4 for samples derived from Idaho rock, Togo rock, and Florida rock, respectively. Phosphogypsum samples subjected to an artificial weathering procedure lost 40% mass, with no change in epsilon. Increasing water content was found to first slightly decrease, then to increase epsilon compared to air-dry samples; epsilon for 100% saturated phosphogypsum was 1.9-fold greater than in air-dry phosphogypsum. Particle size sorting could account for variability of 222Rn exhalation at repositories. Very high moisture contents could slightly increase 222Rn emanation, but exhalation would likely be reduced due to slow diffusion through porosity of saturated phosphogypsum.

  16. Improvement of CT-based treatment-planning models of abdominal targets using static exhale imaging.

    PubMed

    Balter, J M; Lam, K L; McGinn, C J; Lawrence, T S; Ten Haken, R K

    1998-07-01

    CT-based models of the patient that do not account for the motion of ventilation may not accurately predict the shape and position of critical abdominal structures. Respiratory gating technology for imaging and treatment is not yet widely available. The purpose of the current study is to explore an intermediate step to improve the veracity of the patient model and reduce the treated volume by acquiring the CT data with the patients holding their breath at normal exhale. The ventilatory time courses of diaphragm movement for 15 patients (with no special breathing instructions) were measured using digitized movies from the fluoroscope during simulation. A subsequent clinical protocol was developed for treatment based on exhale CT models. CT scans (typically 3.5-mm slice thickness) were acquired at normal exhale using a spiral scanner. The scan volume was divided into two to three segments, to allow the patient to breathe in between. Margins were placed about intrahepatic target volumes based on the ventilatory excursion inferior to the target, and on only the reproducibility of exhale position superior to the target. The average patient's diaphragm remained within 25% of the range of ventilatory excursion from the average exhale position for 42% of the typical breathing cycle, and within 25% of the range from the average inhale position for 15% of the cycle. The reproducibility of exhale position over multiple breathing cycles was 0.9 mm (2sigma), as opposed to 2.6 mm for inhale. Combining the variation of exhale position and the uncertainty in diaphragm position from CT slices led to typical margins of 10 mm superior to the target, and 19 mm inferior to the target, compared to margins of 19 mm in both directions under our prior protocol of margins based on free-breathing CT studies. For a typical intrahepatic target, these smaller volumes resulted in a 3.6% reduction in Veff for the liver. Analysis of portal films shows proper target coverage for patients treated

  17. 8-isoprostane in exhaled breath condensate after experimental exposure to wood smoke in humans.

    PubMed

    Murgia, N; Barregard, L; Sallsten, G; Almstrand, A C; Montuschi, P; Ciabattoni, G; Olin, A C

    2016-01-01

    Wood smoke, a well-known indoor and outdoor air pollutant, may cause adverse health effects through oxidative stress. In this study 8-isoprostane, a biomarker of oxidative stress, was measured in exhaled breath condensate (EBC) and urine before and after experimental exposure to wood smoke. The results were compared with measurements of other biomarkers of oxidative stress and inflammation. Thirteen subjects were exposed first to clean air and then, after 1 week, to wood smoke in an exposure chamber during 4-hour sessions. Exhaled breath condensate, exhaled nitric oxide, blood and urine were sampled before and at various intervals after exposure to wood smoke and clean air. Exhaled breath condensate was examined for 8-isoprostane and malondialdehyde (MDA), while exhaled air was examined for nitric oxide, serum for Clara cell protein (CC16) and urine for 8-isoprostane. 8-isoprostane in EBC did not increase after wood smoke exposure and its net change immediately after exposure was inversely correlated with net changes in MDA (r(s)= -0.57, p= 0.041) and serum CC16 (S-CC16) (r(p)= -0.64, p= 0.020) immediately after the exposure. No correlation was found between 8-isoprostane in urine and 8-isoprostane in EBC. In this study controlled wood smoke exposure in healthy subjects did not increase 8-isoprostane in EBC.

  18. Hydrogen peroxide in exhaled air: a source of error, a paradox and its resolution.

    PubMed

    Peters, Stefan; Kronseder, Angelika; Karrasch, Stefan; Neff, Petra A; Haaks, Matz; Koczulla, Andreas R; Reinhold, Petra; Nowak, Dennis; Jörres, Rudolf A

    2016-04-01

    The concentration of hydrogen peroxide (H2O2) in exhaled air has been reported to be elevated in asthma and chronic obstructive pulmonary disease (COPD), but results are inconsistent and difficult to reproduce. As H2O2 occurs in ambient air, we examined its association with exhaled H2O2 in human subjects. Exhaled breath condensate (EBC) of 12 COPD patients and nine healthy control subjects was collected either with an inhalation filter (efficiency 81%) or without. Ambient air condensate (AAC) was collected in parallel and samples were analysed for H2O2. Additionally, ambient H2O2 was recorded by an atmospheric measuring device (online fluorometric measurement). H2O2 concentration in AAC was significantly higher (p<0.001) than in EBC. AAC variations were concordant with the data from the atmospheric measuring instrument. In both subjects' groups, the inhalation filter reduced H2O2 values (p<0.01). Despite generally low levels in exhaled air, analysis by a mathematical model revealed a contribution from endogenous H2O2 production. The low H2O2 levels in exhaled air are explained by the reconditioning of H2O2-containing inhaled air in the airways. Inhaled H2O2 may be one factor in the heterogeneity and limited reproducibility of study results. A valid determination of endogenous H2O2 production requires inhalation filters.

  19. Diagnostic Chemical Analysis of Exhaled Human Breath Using a Novel Sub-Millimeter Spectroscopic Approach

    NASA Astrophysics Data System (ADS)

    Fosnight, Alyssa M.; Moran, Benjamin L.; Branco, Daniela R.; Thomas, Jessica R.; Medvedev, Ivan R.

    2013-06-01

    As many as 3000 chemicals are reported to be found in exhaled human breath. Many of these chemicals are linked to certain health conditions and environmental exposures. Present state of the art techniques used for analysis of exhaled human breath include mass spectrometry based methods, infrared spectroscopic sensors, electro chemical sensors and semiconductor oxide based testers. Some of these techniques are commercially available but are somewhat limited in their specificity and exhibit fairly high probability of false alarm. Here, we present the results of our most recent study which demonstrated a novel application of a terahertz high resolutions spectroscopic technique to the analysis of exhaled human breath, focused on detection of ethanol in the exhaled breath of a person which consumed an alcoholic drink. This technique possesses nearly ``absolute'' specificity and we demonstrated its ability to uniquely identify ethanol, methanol, and acetone in human breath. This project is now complete and we are looking to extend this method of chemical analysis of exhaled human breath to a broader range of chemicals in an attempt to demonstrate its potential for biomedical diagnostic purposes.

  20. Detection of Lung Cancer with Volatile Organic Biomarkers in Exhaled Breath and Lung Cancer Cells

    NASA Astrophysics Data System (ADS)

    Yu, Jin; Wang, Di; Wang, Le; Wang, Ping; Hu, Yanjie; Ying, Kejing

    2009-05-01

    In patients with lung cancer, volatile organic compounds (VOCs) are excreted in exhaled breath. In this article, exhaled breath of 30 lung cancer paitients and 30 healthy people were collected, preconcentrated by solid-microextraction(SPME) and analyzed with gas chrom-atography and mass spectrometry (GC/MS). A predictive model composed of 5 VOCs out of 16 candidate VOCs detected in the lung cancer patients is constructed by discriminant analysis, with a sensitivity of 76.7% and specificity of 96.7%. We detected exhaled VOCs of 3 different lung cancer cell lines and human bronchial epithelial cell lines. 2-Tridicanone is considered the distinctive marker of lung cancer cells, which is found in lung cancer patients' exhaled breath as well. Compared to healthy people, patients with lung cancer had distinctive VOCs in their exhaled breath. The predictive model can work as diagnosis reference for lung cancer. VOCs found in lung cancer cell line help the cognition of the mechasim VOCs generating in lung cancer patients.

  1. Exhaled nasal nitric oxide output is reduced in humans at night during the sleep period.

    PubMed

    O'Hearn, Daniel J; Giraud, George D; Sippel, Jeffrey M; Edwards, Chad; Chan, Benjamin; Holden, William E

    2007-04-16

    The physiologic function of nasal nitric oxide (NO) release is unknown. In prior experiments, topical NG-nitro-L-arginine methyl ester (L-NAME) on nasal mucosa reduced exhaled nasal NO output and caused daytime sleepiness. We hypothesized that nasal NO output is reduced at night during the sleep period. We measured exhaled nasal NO concentration and minute ventilation and calculated nasal NO output in humans over 24 h. Daytime awake NO output was greater than NO output at night during sleep or transient wakefulness. Exhaled NO concentration decreased during sleep along with minute ventilation. A daytime voluntary reduction in minute ventilation also decreased nasal NO output but exhaled NO concentration increased. Nasal NO output was not changed by body position. We conclude that exhaled nasal NO output is decreased at night due to decreased mass flow of NO into nasal air in addition to decreased minute ventilation. Our findings suggest a role of nasal NO in sleep or in the physiologic processes accompanying sleep.

  2. Use of exhaled air as an improved biomonitoring method to assess perchloroethylene short-term exposure.

    PubMed

    Dias, Cláudia M; Menezes, Helvécio C; Cardeal, Zenilda L

    2017-03-22

    This paper shows the use of exhaled air as a biomonitoring method to assess perchloroethylene (PERC) environmental and occupational exposure. A sensitive, fast, and solvent free analytical method was developed to determine PERC in ambient and exhaled air of individuals occupationally exposed. The developed method used cold fiber solid phase microextraction (CF-SPME) as the sampling technique, and a standard permeation method to simulation of air matrix. The analysis were conducted by gas chromatography coupled to mass spectrometry (GC/MS). The methods were validated and were found to be precise, linear and sensitive for environmental and biological monitoring. The developed methods were applied to twenty-seven sampling points spread across Belo Horizonte city, Brazil, twenty four dry cleaners, an electroplating industry, a research laboratory, and an automotive paint preparation shop. The results of ambient air analyses ranging from 14.0 to 3205.0µgm(-3) with median concentration of 599.0µgm(-3). Furthermore, sampling of exhaled air of individuals occupationally exposed presented results ranging from 6.0 to 2635.0µgm(-3) with median concentration of 325.0µgm(-3). The strong correlation observed between ambient and exhaled air (r =0.930) demonstrates that exhaled air is a suitable biomarker for evaluating occupational exposure to PERC.

  3. Hydrogen peroxide in exhaled air: a source of error, a paradox and its resolution

    PubMed Central

    Peters, Stefan; Kronseder, Angelika; Karrasch, Stefan; Neff, Petra A.; Haaks, Matz; Koczulla, Andreas R.; Reinhold, Petra; Nowak, Dennis

    2016-01-01

    The concentration of hydrogen peroxide (H2O2) in exhaled air has been reported to be elevated in asthma and chronic obstructive pulmonary disease (COPD), but results are inconsistent and difficult to reproduce. As H2O2 occurs in ambient air, we examined its association with exhaled H2O2 in human subjects. Exhaled breath condensate (EBC) of 12 COPD patients and nine healthy control subjects was collected either with an inhalation filter (efficiency 81%) or without. Ambient air condensate (AAC) was collected in parallel and samples were analysed for H2O2. Additionally, ambient H2O2 was recorded by an atmospheric measuring device (online fluorometric measurement). H2O2 concentration in AAC was significantly higher (p<0.001) than in EBC. AAC variations were concordant with the data from the atmospheric measuring instrument. In both subjects' groups, the inhalation filter reduced H2O2 values (p<0.01). Despite generally low levels in exhaled air, analysis by a mathematical model revealed a contribution from endogenous H2O2 production. The low H2O2 levels in exhaled air are explained by the reconditioning of H2O2-containing inhaled air in the airways. Inhaled H2O2 may be one factor in the heterogeneity and limited reproducibility of study results. A valid determination of endogenous H2O2 production requires inhalation filters. PMID:27730191

  4. Comparison of active and passive methods for radon exhalation from a high-exposure building material.

    PubMed

    Abbasi, A; Mirekhtiary, F

    2013-12-01

    The radon exhalation rates and radon concentrations in granite stones used in Iran were measured by means of a high-resolution high purity Germanium gamma-spectroscopy system (passive method) and an AlphaGUARD model PQ 2000 (active method). For standard rooms (4.0 × 5.0 m area × 2.8 height) where ground and walls have been covered by granite stones, the radon concentration and the radon exhalation rate by two methods were calculated. The activity concentrations of (226)Ra in the selected granite samples ranged from 3.8 to 94.2 Bq kg(-1). The radon exhalation rate from the calculation of the (226)Ra activity concentration was obtained. The radon exhalation rates were 1.31-7.86 Bq m(-2)h(-1). The direction measurements using an AlphaGUARD were from 218 to 1306 Bq m(-3) with a mean of 625 Bq m(-3). Also, the exhalation rates measured by the passive and active methods were compared and the results of this study were the same, with the active method being 22 % higher than the passive method.

  5. Influence of environmental concentrations of NO on the exhaled NO test.

    PubMed

    Piacentini, G L; Bodini, A; Vino, L; Zanolla, L; Costella, S; Vicentini, L; Boner, A L

    1998-10-01

    Measurement of levels of exhaled nitric oxide (NO) has been proposed as a noninvasive method for evaluating the degree of airway inflammation in asthmatic patients. Some concern in the interpretation of results of such measurement may arise from possible interference by high environmental concentrations of NO inhaled by these patients. The aim of this study was to verify whether environmental concentrations of NO in the range from 0 to 150 ppb can influence levels of exhaled NO. We tested two groups of subjects. The first group, consisting of 16 subjects, was tested when environmental levels of NO were from 0 to 3 ppb and from 20 to 60 ppb, and exhaled NO mean ppb (+/- SEM) levels were 9.81 +/- 1.43 and 9.78 +/- 1.47 (p = ns) (mean +/- SEM), respectively. The second group, consisting of 30 subjects, was tested at ambient NO concentrations of 0 to 3 ppm, 80 to 100 ppm, and 120 to 150 ppb, and for 18 of these subjects who underwent testing under all three conditions investigated, the mean levels of exhaled NO were 9.23 +/- 1.51, 7.78 +/- 1.19, and 9.33 +/- 1.55 ppb (p = ns), respectively. The results of this study suggest that significantly different ambient levels of NO have no effect on levels of exhaled NO.

  6. A Meta-Analysis of Exhaled Nitric Oxide in Acute Normobaric Hypoxia.

    PubMed

    MacInnis, Martin J; Carter, Eric A; Donnelly, Joseph; Koehle, Michael S

    2015-08-01

    The effect of hypoxia on the exhaled nitric oxide (NO) of humans is unresolved. Many studies have measured the fraction of exhaled NO (FENO) or the partial pressure of exhaled NO (PENO) in normobaric and hypobaric hypoxia, with differing results. To better understand NO physiology and altitude acclimatization, we employed a random effects meta-analysis to determine the effect of acute normobaric hypoxia on the PENO of humans. A total of 93 subjects from 7 published studies (with 9 groups) were included. The median duration of exposure was 30 min and the mean hypoxic PIo2 was 95 (SD=10) mmHg. The weighted standardized mean difference (SMD) in PENO measured at baseline and during an acute exposure to normobaric hypoxia was not significantly different from zero (SMD=0.09; 95% CI=-0.17, 0.34; z=0.65). Based on this meta-analysis, acute normobaric hypoxia does not affect the PENO measured from the mouths of humans. This result should be considered for interpretations of high-altitude (and hypobaric) measurements of exhaled NO. As the PENO is a potential biomarker for altitude-illness susceptibility, recognizing that normobaric hypoxia does not affect the PENO will be important for understanding previous associations between low exhaled NO and poor acclimatization to hypoxia.

  7. Effects of Ginkgo biloba on exhaled nasal nitric oxide during normobaric hypoxia in humans.

    PubMed

    Jowers, Casey; Shih, Richard; James, Jim; Deloughery, Thomas G; Holden, William E

    2004-01-01

    Ginkgo biloba, an extract of the ginkgo tree, may prevent or lessen symptoms of acute mountain sickness in humans. The mechanism of this effect is poorly understood. One hypothesis is that ginkgo alters nitric oxide (NO) metabolism, possibly by scavenging NO or altering nitric oxide synthase expression and thereby lessening the vasodilatory effects of NO. To date, an effect of Ginkgo biloba on NO metabolism has not been demonstrated in humans. We measured exhaled nasal NO output in humans (n = 9) during normoxia and then during acute normobaric hypoxia (goal oxyhemoglobin saturation 75% to 85%) before and after administration of a standardized extract of Ginkgo biloba (120 mg twice daily for 5 days). Oxygen saturation, heart rate, and minute ventilation were similar before and after Ginkgo biloba administration. Exhaled nasal NO output was increased during normoxia following ginkgo (p < 0.02) and reduced during normobaric hypoxia both before (p < 0.02) and following (p < 0.003) ginkgo. Exhaled nasal NO output during normobaric hypoxia was lowest following ginkgo (p < 0.003). We conclude that Ginkgo biloba increases exhaled nasal NO output during normoxia and enhances reduced exhaled nasal NO output during normobaric hypoxia. Our results suggest that Ginkgo biloba may act to reduce AMS through an effect on NO metabolism.

  8. The Effect of Grain Size on Radon Exhalation Rate in Natural-dust and Stone-dust Samples

    NASA Astrophysics Data System (ADS)

    Kumari, Raj; Kant, Krishan; Garg, Maneesha

    Radiation dose to human population due to inhalation of radon and its progeny contributes more than 50% of the total dose from the natural sources which is the second leading cause of lung cancer after smoking. In the present work the dependence of radon exhalation rate on the physical sample parameters of stone dust and natural dust were studied. The samples under study were first crushed, grinded, dried and then passed through sieves with different pore sizes to get samples of various grain sizes (μm). The average value of radon mass exhalation rate is 5.95±2.7 mBqkg-1hr-1 and average value of radon surface exhalation rate is 286±36 mBqm-2 hr-1 for stone dust, and the average value of radon mass exhalation rate is 9.02±5.37 mBqkg-1hr-1 and average value of radon surface exhalation rate is 360±67 mBqm-2 hr-1 for natural dust. The exhalation rate was found to increase with the increase in grain size of the sample. The obtained values of radon exhalation rate for all the samples are found to be under the radon exhalation rate limit reported worldwide.

  9. MIR hollow waveguide (HWG) isotope ratio analyzer for environmental applications

    NASA Astrophysics Data System (ADS)

    Wang, Zhenyou; Zhuang, Yan; Deev, Andrei; Wu, Sheng

    2017-05-01

    An advanced commercial Mid-InfraRed Isotope Ratio (IR2) analyzer was developed in Arrow Grand Technologies based on hollow waveguide (HWG) as the sample tube. The stable carbon isotope ratio, i.e. δ13C, was obtained by measuring the selected CO2 absorption peaks in the MIR. Combined with a GC and a combustor, it has been successfully employed to measure compound specific δ13C isotope ratios in the field. By using both the 1- pass HWG and 5-path HWG, we are able to measure δ13C isotope ratio at a broad CO2 concentration of 300 ppm-37,500 ppm. Here, we demonstrate its applications in environmental studies. The δ13C isotope ratio and concentration of CO2 exhaled by soil samples was measured in real time with the isotope analyzer. The concentration was found to change with the time. We also convert the Dissolved Inorganic Carbon (DIC) into CO2, and then measure the δ13C isotope ratio with an accuracy of better than 0.3 ‰ (1 σ) with a 6 min test time and 1 ml sample usage. Tap water, NaHCO3 solvent, coca, and even beer were tested. Lastly, the 13C isotope ratio of CO2 exhaled by human beings was obtained <10 seconds after simply blowing the exhaled CO2 into a tube with an accuracy of 0.5‰ (1 σ) without sample preconditioning. In summary, a commercial HWG isotope analyzer was demonstrated to be able to perform environmental and health studies with a high accuracy ( 0.3 ‰/Hz1/2 1 σ), fast sampling rate (up to 10 Hz), low sample consumption ( 1 ml), and broad CO2 concentration range (300 ppm-37,500 ppm).

  10. Airway drug pharmacokinetics via analysis of exhaled breath condensate.

    PubMed

    Esther, Charles R; Boucher, Richard C; Johnson, M Ross; Ansede, John H; Donn, Karl H; O'Riordan, Thomas G; Ghio, Andrew J; Hirsh, Andrew J

    2014-02-01

    Although the airway surface is the anatomic target for many lung disease therapies, measuring drug concentrations and activities on these surfaces poses considerable challenges. We tested whether mass spectrometric analysis of exhaled breath condensate (EBC) could be utilized to non-invasively measure airway drug pharmacokinetics and predicted pharmacological activities. Mass spectrometric methods were developed to detect a novel epithelial sodium channel blocker (GS-9411/P-680), two metabolites, a chemically related internal standard, plus naturally occurring solutes including urea as a dilution marker. These methods were then applied to EBC and serum collected from four (Floridian) sheep before, during and after inhalation of nebulized GS-9411/P-680. Electrolyte content of EBC and serum was also assessed as a potential pharmacodynamic marker of drug activity. Airway surface concentrations of drug, metabolites, and electrolytes were calculated from EBC measures using EBC:serum urea based dilution factors. GS-9411/P-680 and its metabolites were quantifiable in the sheep EBC, with peak airway concentrations between 1.9 and 3.4 μM measured 1 h after inhalation. In serum, only Metabolite #1 was quantifiable, with peak concentrations ∼60-fold lower than those in the airway (45 nM at 1 h). EBC electrolyte concentrations suggested a pharmacological effect; but this effect was not statistical significant. Analysis of EBC collected during an inhalation drug study provided a method for quantification of airway drug and metabolites via mass spectrometry. Application of this methodology could provide an important tool in development and testing of drugs for airways diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. [Exhaled nitric oxide levels in school children of Beijing].

    PubMed

    Li, Shuo; Lou, Xiao-shang; Ma, Yu; Han, Sheng-li; Liu, Chuan-he; Chen, Yu-zhi

    2010-02-01

    To learn the normal values of exhaled nitric oxide (eNO) in children. School children in Beijing from 11 to 18 years of age were included in the study. All the students were assigned into two groups: normal group and abnormal group (with allergic disease) according to the International Study of Asthma and Allergy in Childhood questionnaires. eNO, peak expiratory flow rate and sensitization were measured. Totally 395 students were screened out as normal subject (male: 177, female: 218). The eNO level was not significantly different between genders (P > 0.05), but was associated positively with age in both male and female group (P = 0.008 and P = 0.05 respectively) and associated with height in male students (P = 0.02). The geometric mean value of eNO was 11.22 ppb (parts per billion, ppb = 10(9)) in children aged from 11 to 14 years and 14.13 ppb in children aged from 14 to 18 years, with 95% confidence interval 4.17 - 30.20, 5.50 - 36.31 ppb. The eNO level was significantly increased in children who "ever had asthma or wheezing" (n = 68), and children who "ever had rhinitis" (n = 96) compared with normal subjects (P = 0.001 and P = 0.008). The geometric mean value of eNO was 16.98 ppb in children with positive skin prick test and was significantly increased as compared with children with negative skin prick test with eNO level at 11.75 ppb (P = 0.001). eNO level varied between 10.72 ppb and 13.80 ppb in normal children 11 - 18 years of age, and was positively associated with age and height, but not with gender. eNO level increased significantly in children with wheezing and atopy.

  12. Natural radioactivity and radon exhalation rate in Brazilian igneous rocks.

    PubMed

    Moura, C L; Artur, A C; Bonotto, D M; Guedes, S; Martinelli, C D

    2011-07-01

    This paper reports the natural radioactivity of Brazilian igneous rocks that are used as dimension stones, following the trend of other studies on the evaluation of the risks to the human health caused by the rocks radioactivity as a consequence of their use as cover indoors. Gamma-ray spectrometry has been utilized to determine the (40)K, (226)Ra and (232)Th activity concentrations in 14 rock types collected at different quarries. The following activity concentration range was found: 12.18-251.90 Bq/kg for (226)Ra, 9.55-347.47 Bq/kg for (232)Th and 407.5-1615.0 Bq/kg for (40)K. Such data were used to estimate Ra(eq), H(ex) and I(γ), which were compared with the threshold limit values recommended in literature. They have been exceeded for Ra(eq) and H(ex) in five samples, where the highest indices corresponded to a rock that suffered a process of ductile-brittle deformation that caused it a microbrecciated shape. The exhalation rate of Rn and daughters has also been determined in slabs consisting of rock pieces ~10 cm-long, 5 cm-wide and 3 cm-thick. It ranged from 0.24 to 3.93 Bq/m(2)/h and exhibited significant correlation with eU (=(226)Ra), as expected. The results indicated that most of the studied rocks did not present risk to human health and may be used indoors, even with low ventilation. On the other hand, igneous rocks that yielded indices above the threshold limit values recommended in literature may be used outdoors without any restriction or indoors with ample ventilation.

  13. Exhaled carbon monoxide in asthmatics: a meta-analysis

    PubMed Central

    2010-01-01

    Background The non-invasive assessment of airway inflammation is potentially advantageous in asthma management. Exhaled carbon monoxide (eCO) measurement is cheap and has been proposed to reflect airway inflammation and oxidative stress but current data are conflicting. The purpose of this meta-analysis is to determine whether eCO is elevated in asthmatics, is regulated by steroid treatment and reflects disease severity and control. Methods A systematic search for English language articles published between 1997 and 2009 was performed using Medline, Embase and Cochrane databases. Observational studies comparing eCO in non-smoking asthmatics and healthy subjects or asthmatics before and after steroid treatment were included. Data were independently extracted by two investigators and analyzed to generate weighted mean differences using either a fixed or random effects meta-analysis depending upon the degree of heterogeneity. Results 18 studies were included in the meta-analysis. The eCO level was significantly higher in asthmatics as compared to healthy subjects and in intermittent asthma as compared to persistent asthma. However, eCO could not distinguish between steroid-treated asthmatics and steroid-free patients nor separate controlled and partly-controlled asthma from uncontrolled asthma in cross-sectional studies. In contrast, eCO was significantly reduced following a course of corticosteroid treatment. Conclusions eCO is elevated in asthmatics but levels only partially reflect disease severity and control. eCO might be a potentially useful non-invasive biomarker of airway inflammation and oxidative stress in nonsmoking asthmatics. PMID:20433745

  14. Elevated exhaled nitric oxide in anaphylaxis with respiratory symptoms.

    PubMed

    Nakamura, Yoichi; Hashiba, Yoko; Endo, Jyunji; Furuie, Masashi; Isozaki, Atsushi; Yagi, Kei-ichi

    2015-10-01

    Anaphylaxis is a serious type I allergic reaction that occurs suddenly and can result in death, but it is sometimes difficult to differentiate from other diseases, and physicians must rely on symptoms alone for its diagnosis. Meanwhile, fractional exhaled nitric oxide (FeNO) concentration, used in assessing airway inflammation in bronchial asthma, is known to be affected by atopic disposition. The possible role of FeNO measurements was evaluated in patients with anaphylaxis. FeNO was measured in 52 adult patients (17-78 years old, median age 41.5 years) in whom anaphylaxis occurred. These measurements were made within 24 h after onset and after about one month when the patients were symptom-free. In some of these patients, FeNO was measured a third time, two months or more after onset. The FeNO level in the 52 patients was not significantly different in measurement made within 24 h of onset of anaphylaxis and after one month. However, excluding 9 patients who also had asthma history, the FeNO level in the remaining 43 patients decreased significantly from within 24 h of onset (36.7 ± 27.5 ppb) to one month later (28.8 ± 19.5 ppb). Of these 43 patients, this phenomenon was evident in a group that had respiratory symptoms (31 patients), but it was not seen in a group that did not have respiratory symptoms (12 patients). Elevation of FeNO was related to respiratory symptoms observed in anaphylactic patients without asthma. Although the mechanism of increased FeNO level is unclear, its usefulness for diagnosis of anaphylaxis must be examined in prospective studies. Copyright © 2015 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

  15. Methodological aspects of exhaled nitric oxide measurements in infants.

    PubMed

    Gabriele, Carmelo; van der Wiel, Els C; Nieuwhof, Eveline M; Moll, Henriette A; Merkus, Peter J F M; de Jongste, Johan C

    2007-02-01

    Guidelines for the measurement of fractional exhaled nitric oxide (FE(NO)) recommend refraining from lung function tests (LFT) and certain foods and beverages before performing FE(NO) measurements, as they may lead to transiently altered FE(NO) levels. Little is known of such factors in infants. The aim of the present study was to evaluate whether forced expiratory maneuvers, sedation, nasal contamination, and breastfeeding affect FE(NO) values in infants. FE(NO) was measured off-line during tidal breathing by means of a facemask covering nose and mouth. FE(NO) measurements were performed in 45 sedated infants (mean age 12.1 months) who underwent LFT because of airway diseases and in 83 unsedated healthy infants (mean age 4.3 months). In infants with airway diseases, no difference was found in FE(NO) values before and 5 min after LFT (n = 19 infants, p = 0.7) and FE(NO) values before sedation did not differ from FE(NO) values during sedation (n = 10 infants, p = 0.2). Oral FE(NO) values were significantly lower than mixed (nasal + oral) FE(NO) (n = 42 infants, p < 0.001). FE(NO) values before and 5 min after breastfeeding were not different (n = 11 healthy infants, p = 0.57). The short-term reproducibility in healthy infants (n = 54) was satisfactory (intraclass correlation coefficient = 0.94). We conclude that, in infants with airway diseases, LFT prior to FE(NO) measurement did not influence FE(NO) values and FE(NO) values did not change after sedation. Oral FE(NO) values were significantly lower than mixed (oral + nasal) FE(NO), and breastfeeding did not influence FE(NO). Short-term reproducibility in awake healthy infants was good.

  16. Nasal and exhaled nitric oxide in chronic rhinosinusitis with polyps.

    PubMed

    Jeong, Jin Hyeok; Yoo, Han Seok; Lee, Seung Hwan; Kim, Kyung Rae; Yoon, Ho Joo; Kim, Sang Heon

    2014-01-01

    The ciliary epithelial cells in the paranasal sinuses produce nasal nitric oxide (NO) continuously and plays a variety of roles in the paranasal sinuses. The purpose of this study was to assess whether we can use the levels of nasal NO (nNO) and exhaled NO (eNO) as a tool for evaluation in chronic rhinosinusitis (CRS) with nasal polyp patients. We used chemiluminescent NO analyzer to measure nNO and eNO among normal controls (32) and CRS with polyp (30) and CRS with polyp and allergic rhinitis patients (27) and compared it with various clinical symptoms, laboratory data, and computed tomography (CT) scores. Levels of nNO were significantly lower in patients with CRS with polyps (88.5 ± 54.7 ppb) compared with controls (241.0 ± 89.5 ppb). Levels of nNO in CRS with polyps and allergic rhinitis (167.0 ± 47.6 ppb) were significantly higher than CRS with polyps and lower than controls. A significant inverse relationship was observed between nNO and sinus CT scores, severity of nasal obstruction, and purulent rhinorrhea in CRS with polyps. Low values of nNO separated well patients with CRS with polyps, and the cutoff value of <163 ppb was associated with the best combination of specificity (93%) and sensitivity (81%). A significant positive relationship was observed between eNO and CT scores. The nNO could be used for another screening of CRS with polyps for the more severe phenotypes, which may eventually have to be treated with surgery.

  17. Spirometry filters can be used to detect exhaled respiratory viruses.

    PubMed

    Mitchell, Alicia B; Mourad, Bassel; Tovey, Euan; Buddle, Lachlan; Peters, Matthew; Morgan, Lucy; Oliver, Brian G

    2016-09-26

    Respiratory viruses are very common in the community and contribute to the burden of illness for patients with chronic respiratory diseases, including acute exacerbations. Traditional sampling methods are invasive and problematic to repeat. Accordingly, we explored whether respiratory viruses could be isolated from disposable spirometry filters and whether detection of viruses in this context represented presence in the upper or lower respiratory tract. Discovery (n  =  53) and validation (n  =  49) cohorts were recruited from a hospital outpatient department during two different time periods. Spirometry mouthpiece filters were collected from all participants. Respiratory secretions were sampled from the upper and lower respiratory tract by nasal washing (NW), sputum, and bronchoalveolar lavage (BAL). All samples were examined using RT-PCR to identify a panel of respiratory viruses (rhinovirus, respiratory syncytial virus, influenza A, influenza B, parainfluenza virus 1, 2 & 3, and human metapneumovirus). Rhinovirus was quantified using qPCR. Paired filter-NW samples (n  =  29), filter-sputum samples (n  =  24), filter-BAL samples (n  =  39) and filter-NW-BAL samples (n  =  10) provided a range of comparisons. At least one virus was detected in any sample in 85% of participants in the discovery cohort versus 45% in the validation cohort. Overall, 72% of viruses identified in the paired comparator method matched those detected in spirometry filters. There was a high correlation between viruses identified in spirometry filters compared with viruses identified in both the upper and lower respiratory tract using traditional sampling methods. Our results suggest that examination of spirometry filters may be a novel and inexpensive sampling method for the presence of respiratory viruses in exhaled breath.

  18. Determinants of exhaled nitric oxide in chronic rhinosinusitis.

    PubMed

    Guida, Giuseppe; Rolla, Giovanni; Badiu, Iuliana; Marsico, Pietro; Pizzimenti, Stefano; Bommarito, Luisa; De Stefani, Antonella; Usai, Antonio; Bugiani, Massimiliano; Malinovschi, Andrei; Bucca, Caterina; Heffler, Enrico

    2010-03-01

    Chronic rhinosinusitis (CRS) has been reported to be associated with increased values of exhaled nitric oxide (ENO), which could not be entirely explained by the association between CRS and asthma. The aim of this study was to investigate the variables associated with increased ENO in patients with CRS. This was a prospective cross-sectional descriptive study of 93 consecutive patients with CRS. The effect on ENO of age, gender, atopy, asthma, respiratory symptoms without bronchial hyperresponsiveness (BHR), and nasal polyps was evaluated by multiple regression analysis. Nasal polyps (P = .01), asthma (P < .001), and respiratory symptoms without BHR (P = .01) were the only independent variables associated with increased ENO. The prevalence of asthma was significantly higher in subjects with nasal polyps (61% vs 29.4%), P = .005, whereas the prevalence of respiratory symptoms without BHR was higher in those without nasal polyps (44.1% vs 15.3%, P = .003). Respiratory symptoms without BHR were associated with significantly higher ENO and prevalence of sputum eosinophilia (eosinophils > 3%) in patients with nasal polyps compared with those without nasal polyps (68.2 vs 24.0 ppb, P = .001; 60% vs 8.3%, P = .03, respectively). The presence of nasal polyps in patients with CRS was associated with increased asthma prevalence as well as increased ENO levels. Respiratory symptoms without BHR were associated with eosinophilic airway inflammation and increased ENO only in patients with nasal polyps. These findings suggest important clinical and biologic differences between the two types of CRS, with and without nasal polyps.

  19. Exhaled breath condensate pH in mechanically ventilated patients.

    PubMed

    Nannini, L J; Quintana, R; Bagilet, D H; Druetta, M; Ramírez, M; Nieto, R; Guelman Greta, G

    2013-12-01

    In this prospective clinical trial we aimed to answer if spontaneous exhaled breath condensate (EBC) in the trap of the expiratory arm of the ventilator could replace EBC collected by coolant chamber standardized with Argon as an inert gas. Second, if EBC pH could predict ventilator associated pneumonia (VAP) and mortality. We included 34 critically ill patients (males = 26), aged = 54.85 ± 19.86 (mean ± SD) yrs, that required mechanical ventilation due to non-pulmonary direct cause (APACHE II score = 23.58 ± 14.7; PaO(2)/FiO(2) = 240.00 ± 98.29). ICU with 9 beds from a regional teaching hospital. The patients were followed up until development of VAP, successful weaning or death. There were significant differences between mean EBC pH from the 4 procedures with the exception of spontaneous EBC de-aerated with Argon (n = 79; 6.74 ± 0.28) and coolant chamber deaerated with Argon (n = 79; 6.70 ± 0.36; p = NS by Tukey's Multiple Comparison Test). However, none of the procedures were extrapolated between each other according to Bland & Altman method. The mean EBC pH from the trap without Argon was 6.50 ± 0.28. From the total of 34 patients, 22 survived and were discharged and 12 patients died in the ICU. Spontaneous EBC pH could not be extrapolated to EBC pH from coolant chamber and it did not change in subjects who dead, neither subject with VAP in comparison with baseline data. The lack of other biomarker in EBC and the lack of a control group determinate the need for further studies in this setting. Copyright © 2012 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  20. Complementary system for long term measurements of radon exhalation rate from soil

    SciTech Connect

    Mazur, J.; Kozak, K.

    2014-02-15

    A special set-up for continuous measurements of radon exhalation rate from soil is presented. It was constructed at Laboratory of Radiometric Expertise, Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN), Krakow, Poland. Radon exhalation rate was determined using the AlphaGUARD PQ2000 PRO (Genitron) radon monitor together with a special accumulation container which was put on the soil surface during the measurement. A special automatic device was built and used to raise and lower back onto the ground the accumulation container. The time of raising and putting down the container was controlled by an electronic timer. This set-up made it possible to perform 4–6 automatic measurements a day. Besides, some additional soil and meteorological parameters were continuously monitored. In this way, the diurnal and seasonal variability of radon exhalation rate from soil can be studied as well as its dependence on soil properties and meteorological conditions.

  1. A breath sampling system assessing the influence of respiratory rate on exhaled breath composition.

    PubMed

    Lomonaco, T; Salvo, P; Ghimenti, S; Biagini, D; Bellagambi, F; Fuoco, R; Di Francesco, F

    2015-01-01

    This work presents a computerized system to monitor mouth pressure, tidal volume, exhaled airflow, respiration rate and end-tidal partial pressure of CO2 during breath collection. The system was used to investigate the effect of different respiratory rates on the volatile organic compounds (VOCs) concentrations in exhaled breath. For this purpose, VOCs with well-defined biochemical pathways and different chemical and physical properties were selected as biomarkers related to metabolism (acetone and isopropyl alcohol), cholesterol synthesis (isoprene) and intestinal microflora activity (ethanol). Mixed breath was collected from a nominally healthy volunteer in resting conditions by filling a Nalophan bag. The subject followed a regimented breathing pattern at different respiratory rates (10, 30 and 50 breaths per minute). Results highlight that ventilation pattern strongly influences the concentration of the selected compounds. The proposed system allows exhaled breath to be collected also in patients showing dyspnea such as in case of chronic heart failure, asthma and pulmonary diseases.

  2. Application of thermal desorption to the biological monitoring of organic compounds in exhaled breath.

    PubMed

    Periago, J F; Prado, C; Ibarra, I; Tortosa, J

    1993-12-24

    We have developed a thermal desorption-gas chromatographic method for the analysis of organic compounds in exhaled breath air, to be used in the biological monitoring of environmental exposure. The exhaled breath sampler is based on the concentration of compounds present in alveolar air in a solid sorbent material. Isoflurane (1-chloro-2,2,2-trifluoroethyl-difluoromethyl-ether), an inhaled anaesthetic used widely in surgery, and styrene, used in boat construction and the manufacture of fibreglass-reinforced plastics, are partially eliminated from the body in exhaled breath, samples of which can therefore be used to monitor biological exposure to these two organic compounds. Recoveries were tested in controlled atmospheres of isoflurane or styrene, with Chromosorb 106 or Tenax, respectively, as the adsorbent. We also investigated the influence of relative humidity, an important factor in breath sampling, on adsorption.

  3. Radon exhalation from sub-slab aggregate used in home construction in Canada.

    PubMed

    Bergman, Lauren; Lee, Jaeyoung; Sadi, Baki; Chen, Jing

    2015-06-01

    Exposure to elevated levels of radon in homes has been shown to result in an increased risk of developing lung cancer. The two largest contributors to indoor radon are radon in soil gas, formed from the rocks and soil surrounding the home, and building materials such as aggregate. This study measured the surface radon exhalation rates for 35 aggregate samples collected from producers across Canada. The radon exhalation rates ranged from 2.3 to 479.9 Bq m(-2) d(-1), with a mean of 80.7±112 Bq m(-2) d(-1). Using a simple, conservative analysis, the aggregate contribution to radon concentrations in an unfinished basement was determined. The maximum estimated radon concentration was 32.5±2.7 Bq m(-3), or ~16 % of the Canadian Radon Guideline. It can be concluded that under normal conditions radon exhalation from aggregate contributes very little to the total radon concentration in indoor air.

  4. Natural radioactivity and radon exhalation rate of soil in southern Egypt.

    PubMed

    Sroor, A; El-Bahi, S M; Ahmed, F; Abdel-Haleem, A S

    2001-12-01

    The level of natural radioactivity in soil of 30 mining samples collected from six locations in southern Egypt was measured. Concentrations of radionuclides in samples were determined by gamma-ray spectrometer using HPGe detector with a specially designed shield. The obtained results of uranium and thorium series as well as potassium (K-40) are discussed. The present data were compared with data obtained from different areas in Egypt. Also, a solid state nuclear track detector SSNTD (Cr-39) was used to measure the radon concentration as well as exhalation rate for these samples. The radon concentrations were found to vary from 1.54 to 5.37 Bq/kg. The exhalation rates were found to vary from 338.81 to 1426.47 Bq/m2d. The values of the radon exhalation rate are found to correspond with the uranium concentration values measured by the germanium detector in the corresponding soil samples.

  5. Gas chromatography/mass spectrometry analysis of exhaled leukotrienes in asthmatic patients

    PubMed Central

    Cap, P; Chladek, J; Pehal, F; Maly, M; Petru, V; Barnes, P; Montuschi, P

    2004-01-01

    Background: Leukotriene-like immunoreactivity has been detected in exhaled breath condensate (EBC), but definitive evidence for the presence of leukotrienes (LTs) in this biological fluid is not available. A study was undertaken to determine whether LTC4, LTD4, LTE4, and LTB4 are measurable in EBC by gas chromatography/mass spectrometry and to quantify exhaled LTs in adults and children with asthma and in control subjects. Methods: Twenty eight adults and 33 children with mild to moderate persistent asthma treated with inhaled corticosteroids and age matched healthy controls (50 adults and 50 children) were studied. LTB4, LTC4, LTD4, and LTE4 in EBC were measured by gas chromatography/mass spectrometry. Results: LTD4, LTE4, and LTB4 were detectable in all samples. Concentrations of LTC4 in EBC were either close to or below the detection limit of 1 pg/ml. Median exhaled LTD4, LTE4, and LTB4 concentrations in asthmatic adults were increased 4.1-fold (p<0.001), 1.8-fold (p<0.01), and 2.6-fold (p<0.001), respectively, compared with values in healthy adults. Median exhaled LTD4, LTE4, and LTB4 concentrations in asthmatic children were increased 2.8-fold (p<0.001), 1.3-fold (p<0.001), and 1.6-fold (p<0.001), respectively, compared with those in healthy children. In patients with asthma there was a correlation between exhaled LTD4 and LTE4 in both adults (r = 0.87, p<0.0001) and children (r = 0.78, p<0.0001). Conclusions: Gas chromatography/mass spectrometry can be used to accurately quantify exhaled LTs which are increased in asthmatic adults and children compared with controls. PMID:15170025

  6. [Exhale nitric oxide (NO) and respiratory function measured with body plethysmography in children].

    PubMed

    Storme, L; Riou, Y; Leclerc, F; Dubois, A; Deschildre, A; Pierre, M H; Logier, R; Robin, H; Lequien, P

    1998-04-01

    Exhaled nitric oxide (NO) may be a marker of airway inflammation. Previous studies in adults have shown that the level of NO in exhaled air is influenced by several factors (breath holding, exercise, etc), or by several disease (asthma, congestive heart failure, diseases of the upper respiratory tract, cystic fibrosis, etc). However, few studies have been performed in children less than 3 years of age. The aim of this study was to determine endogenous NO levels in children with various diseases during lung volume measurements. Fifty-two children aged 18.3 +/- 9.5 months were studied. The population was divided in two groups, according to the underlying disease: a group of 39 children with cystic fibrosis (n = 7), bronchopulmonary dysplasia (n = 17), asthma (n = 7) or recurrent respiratory tract infections (n = 8) and a second group of 13 children without respiratory disease. Lung function was measured by whole body plethysmography and several respiratory parameters were calculated (functional residual capacity [FRC], compliance and resistances of the respiratory system, trapped volume). NO production was measured on a chemiluminescence analyzer from mixed exhaled air collected into a bag, over a period of 5 minutes. NO production was related to disease: exhaled NO levels were three times higher in bronchopulmonary dysplasia and cystic fibrosis, compared to NO levels in children without respiratory disease. They were higher in asthma. They were not altered in recurrent respiratory tract infections. No correlation was found between respiratory parameters and NO production. However, exhaled NO levels were correlated to trapped volume, which defined dynamic part of pulmonary hyperinflation. Levels of endogenous NO in infants were similar to those measured in adults with and without inflammatory respiratory disease. Lung distention influenced exhaled NO production.

  7. Diagnostic significance of nitric oxide concentrations in exhaled air from the airways in allergic rhinitis patients

    PubMed Central

    Krzych-Fałta, Edyta; Samoliński, Bolesław K; Zalewska, Marta

    2016-01-01

    Introduction The effect of nitric oxide (NO) on the human body is very important due its physiological regulation of the following functions of airways: modulation of ciliary movement and maintenance of sterility in sinuses. Aim To evaluate the diagnostic significance of NO concentrations in exhaled air from the upper and lower airways in patients diagnosed with allergic rhinitis (AR). Material and methods The subjects included in the study were a group of 30 people diagnosed with sensitivity to environmental allergens and a control group consisting of 30 healthy subjects. The measurement of NO in the air exhaled from the lower and upper airways was performed using an on-line method by means of Restricted Exhaled Breath (REB), as well as using the measurement procedure (chemiluminescence) set out in the guidelines prepared in 2005 by the American Thoracic Society and the European Respiratory Society. Results In the late phase of the allergic reaction, higher values of the level of exhaled NO concentration from the lower airways were observed in the groups of subjects up to the threshold values of 25.17 ppb in the group of subjects with year-round allergic rhinitis and 21.78 ppb in the group with diagnosed seasonal allergic rhinitis. The difference in the concentration of NO exhaled from the lungs between the test group and the control group in the 4th h of the test was statistically significant (p = 0.045). Conclusions Exhaled NO should be considered as a marker of airway inflammation. It plays an important role in the differential diagnosis of allergy. PMID:27279816

  8. Effects of condensate in the exhalation limb of neonatal circuits on airway pressure during bubble CPAP.

    PubMed

    Youngquist, Tiffany M; Richardson, C Peter; Diblasi, Robert M

    2013-11-01

    Bubble CPAP is frequently used in spontaneously breathing infants with lung disease. Often bubble CPAP systems lack pressure alarms and pressure-release valves. We observed a large volume of condensate in the exhalation limb of a patient circuit and conducted a series of experiments to test the hypothesis that accumulated condensate could affect delivered pressures. An anatomically accurate nasal airway model of a preterm infant was attached to a spontaneously breathing lung model. A bubble CPAP system was attached to the nasal airway with bi-nasal short prongs, and the rate of fluid condensation was measured. Next, tracheal pressures were monitored digitally to detect changes in airway pressure related to condensate accumulation. Measurements were obtained with volumes of 0, 5, 10, 15, and 20 mL of water in the exhalation limb, at flows of 4, 6, 8, and 10 L/min. Measurements with 20 mL in the exhalation limb were recorded with and without a pressure-relief valve in the circuit. The rate of condensate accumulation was 3.8 mL/h. At volumes of ≥ 10 mL, noticeable alterations in the airway pressure waveforms and significant increases in mean tracheal pressure were observed. The pressure-relief valve effectively attenuated peak tracheal pressure, but only decreased mean pressure by 0.5-1.5 cm H2O. Condensate in the exhalation limb of the patient circuit during bubble CPAP can significantly increase pressure delivered to the patient. The back and forth movement of this fluid causes oscillations in airway pressure that are much greater than the oscillations created by gas bubbling out the exhalation tube into the water bath. We recommend continuously monitoring pressure at the nasal airway interface, placing an adjustable pressure-relief valve in the circuit, set to 5 cm H2O above the desired mean pressure, and emptying fluid from the exhalation limb every 2-3 hours.

  9. Exhaled breath condensate pH decreases during exercise-induced bronchoconstriction.

    PubMed

    Bikov, Andras; Galffy, Gabriella; Tamasi, Lilla; Bartusek, Dora; Antus, Balazs; Losonczy, Gyorgy; Horvath, Ildiko

    2014-05-01

    Exercise-induced bronchoconstriction (EIB) is the temporary narrowing of the airways caused by physical exercise. Its exact pathophysiology is unclear; however, acute changes in airways pH may play a role. Exhaled breath condensate (EBC) pH was suggested as a surrogate indicator for airway acid-base status, but its value is also affected by volatile molecules and respiratory droplet dilution. The aim of the study was to assess changes in EBC pH during EIB. Twenty-two asthmatics who reported breathlessness following exercise and 16 healthy individuals participated in the study. Lung function test was performed and exhaled breath samples were collected for pH, dilution factor and volatile compound pattern measurements (Cyranose 320) pre-exercise and at 0, 10, 20 and 30 min after physical exercise challenge. Fractional exhaled nitric oxide was measured before exercise. EIB developed in 13 asthmatic subjects. In these participants, but not in the EIB-negative asthmatics (P = 0.51), EBC pH reduced significantly during exercise (P = 0.01). In addition, changes in EBC pH were related to the degree of bronchospasm in the EIB-positive group (P = 0.01, r = 0.68). Exhaled volatile pattern became altered (P < 0.05) during exercise in all subjects (asthmatics and controls). EBC pH changes were not related to EBC dilution or volatile compound pattern alterations (P > 0.05). The development of EIB was related to acute changes of EBC pH, which suggest the role of airway pH decrease in the pathophysiology of EIB. Exercise-induced changes in exhaled biomarkers suggest methodological precautions to avoid physical exercise before performing exhaled breath tests. © 2014 The Authors. Respirology © 2014 Asian Pacific Society of Respirology.

  10. Exhaled Breath Condensate Eicosanoid Levels Associate with Asthma and its Severity

    PubMed Central

    Kazani, Shamsah; Planaguma, Anna; Ono, Emiko; Bonini, Matteo; Zahid, Muhammad; Marigowda, Gautham; Wechsler, Michael E.; Levy, Bruce D.; Israel, Elliot

    2013-01-01

    Background The relationship between anti-inflammatory lipoxins and pro-inflammatory leukotrienes may be important in the pathobiology of asthma and its severity. Objective To investigate whether exhaled breath condensate (EBC) lipoxin and leukotriene measurements can non-invasively characterize the asthmatic diathesis and its severity. Methods We measured lipoxin A4 (LXA4) and leukotriene B4 (LTB4) levels in EBC collected from asthmatics of different severities and from healthy controls. Results EBC LXA4 and LTB4 levels are elevated in asthmatics as compared to healthy controls (LXA4 31.40 vs. 2.41 pg/ml EBC respectively, p < 0.001; LTB4 45.62 vs. 3.82 pg/ml EBC, p < 0.001). While both eicosanoids are elevated in asthmatics, the ratio LXA4 to LTB4 decreases with increasing asthma severity. It is 41% lower in severe versus moderate asthmatics (0.52 vs. 0.88, p = 0.034). EBC LXA4 levels correlate with the degree of airflow obstruction measured by FEV1 (r = 0.28, p = 0.018). A cut-off value of 7 pg LXA4/ml EBC provides 90% sensitivity and 92% specificity for the diagnosis of asthma (AUC 0.96, p < 0.001). A cut-off value of 11 pg LTB4/ml EBC provides 100% sensitivity and 100% specificity for the diagnosis of asthma (AUC 1, p < 0.001). Conclusions Pro-resolving and pro-inflammatory eicosanoids are generated in airways of all asthmatics. The proportion of pro-resolving compounds declines with asthma severity. These findings support the role for EBC eicosanoid measurements in the non-invasive diagnosis of asthma and suggest that pro-resolving eicosanoid pathways are dys-regulated in severe asthma. PMID:23608729

  11. Increase in exhaled nitric oxide is associated with bronchial hyperresponsiveness among apprentices.

    PubMed

    Tossa, Paul; Paris, Christophe; Zmirou-Navier, Denis; Demange, Valérie; Acouetey, Dovi-Stéphanie; Michaely, Jean-Pierre; Bohadana, Abraham

    2010-09-15

    Airway inflammation is a hallmark of asthma. Several studies have validated the use of the fractional concentration of exhaled nitric oxide (Fe(NO)) as a surrogate marker of airway inflammation in asthma. We examined how the change in Fe(NO) levels, since the beginning of occupational exposure, could be associated with the incidence of bronchial hyperresponsiveness (BHR) among baker, pastry maker, and hairdresser apprentices during their 2-year training. A standardized questionnaire was administered; skin prick tests for common and specific occupational allergens were done; methacholine challenge and measurement of Fe(NO) were performed 6, 12, and 15 months after the first examination. Of 441 apprentices initially included, 351 completed the study. The increase in Fe(NO), since the beginning of exposure, was associated with the incidence of BHR (odds ratio, 2.00 [95% confidence interval, 1.21-3.32] per unit increase in log parts per billion) both in atopic and nonatopic subjects. The average increase in Fe(NO) was similar in atopic and nonatopic subjects and was unrelated to past or current smoking habits, sex, or training track. Atopy in bakers/pastry makers and sensitization to alkaline persulfates in hairdressers were also independently associated with the incidence of BHR. BHR occurred sooner among bakers/pastry makers than among hairdressers, but its incidence leveled off later. Our results suggest that measurement of Fe(NO), a simple and reproducible test, could be useful in the screening of BHR in workers newly exposed to agents known to cause occupational asthma.

  12. Reference values of fractional excretion of exhaled nitric oxide among non-smokers and current smokers.

    PubMed

    Torén, Kjell; Murgia, Nicola; Schiöler, Linus; Bake, Björn; Olin, Anna-Carin

    2017-08-25

    Fractional exhaled nitric oxide (FENO) is used to assess of airway inflammation; diagnose asthma and monitor adherence to advised therapy. Reliable and accurate reference values for FENO are needed for both non-smoking and current smoking adults in the clinical setting. The present study was performed to establish reference adult FENO values among never-smokers, former smokers and current smokers. FENO was measured in 5265 subjects aged 25-75 years in a general-population study, using a chemiluminescence (Niox ™) analyser according to the guidelines of the American Thoracic Society and the European Respiratory Society. Atopy was based on the presence of immunoglobulin E (IgE) antibodies to common inhalant allergens (measured using Phadiatop® test). Spirometry without bronchodilation was performed and forced vital capacity (FVC), forced expired volume in 1 s (FEV1) and the ratio of FEV1 to FVC values were obtained. After excluding subjects with asthma, chronic bronchitis, spirometric airway obstruction and current cold, 3378 subjects remained. Equations for predictions of FENO values were modelled using nonparametric regression models. FENO levels were similar in never-smokers and former smokers, and these two groups were therefore merged into a group termed "non-smokers". Reference equations, including the 5th and 95th percentiles, were generated for female and male non-smokers, based on age, height and atopy. Regression models for current smokers were unstable. Hence, the proposed reference values for current smokers are based on the univariate distribution of FENO and fixed cut-off limits. Reference values for FENO among respiratory healthy non-smokers should be outlined stratified for gender using individual reference values. For current smokers separate cut-off limits are proposed.

  13. Obesity disproportionately impacts lung volumes, airflow and exhaled nitric oxide in children.

    PubMed

    Yao, Tsung-Chieh; Tsai, Hui-Ju; Chang, Su-Wei; Chung, Ren-Hua; Hsu, Jing-Ya; Tsai, Ming-Han; Liao, Sui-Ling; Hua, Man-Chin; Lai, Shen-Hao; Chen, Li-Chen; Yeh, Kuo-Wei; Tseng, Yu-Lun; Lin, Wan-Chen; Chang, Su-Ching; Huang, Jing-Long

    2017-01-01

    The current literature focusing on the effect of obesity and overweight on lung function and fraction of exhaled nitric oxide (FeNO) in children, particularly among healthy children of non-European descent, remains controversial. Furthermore, whether the relationship of obesity and overweight with lung function and FeNO in children is modified by atopy is unclear. The objective of this study was to examine the effect of excess weight on lung function parameters and FeNO among Asian children, with a particular focus on exploring the potential effect modification by atopy. We investigated the effect of excess weight on lung function and FeNO in a population sample of 1,717 children aged 5 to 18 years and explored the potential modifying effect of atopy. There were positive associations of body mass index (BMI) z-score with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), and forced expiratory flow at 25-75% (FEF25-75) (all P<0.001), after controlling for confounders. The beta coefficient for FEV1 (0.084) was smaller than that for FVC (0.111). In contrast, a negative association was found between BMI z-score and FEV1/FVC ratio (P<0.001) and FeNO (P = 0.03). A consistent pattern of association for lung function variables was observed when stratifying by atopy. There was a negative association of BMI z-score with FeNO in atopic subjects (P = 0.006), but not in non-atopic subjects (P = 0.46). Excess weight disproportionately impacts lung volumes and airflow in children from the general population, independent of atopic status. Excess weight inversely affects FeNO in atopic but not in non-atopic children.

  14. Chemical analysis of exhaled human breath using a terahertz spectroscopic approach

    NASA Astrophysics Data System (ADS)

    Fosnight, Alyssa M.; Moran, Benjamin L.; Medvedev, Ivan R.

    2013-09-01

    As many as 3500 chemicals are reported in exhaled human breath. Many of these chemicals are linked to certain health conditions and environmental exposures. This experiment demonstrated a method of breath analysis utilizing a high resolution spectroscopic technique for the detection of ethanol, methanol, and acetone in the exhaled breath of a person who consumed alcohol. This technique is applicable to a wide range of polar molecules. For select species, unambiguous detection in a part per trillion dilution range with a total sample size in a femtomol range is feasible. It compares favorably with other methods of breath analysis.

  15. Detection of ammonia in exhaled breath for clinical diagnosis- A review

    NASA Astrophysics Data System (ADS)

    Gafare, Mawahib; Dennis, J. O.; Md Khir, M. H.

    2014-10-01

    This paper presents ammonia gas as a biomarker for different clinical conditions when it exceeds the normal concentration in the exhaled breath. In peculiar, detection of ammonia in human breath has the effort to investigate various practicabilities inclusive those comprising the kidneys, liver and bacterial infection of either the stomach or mouth. Laser spectroscopy, gas chromatography, photo-acoustic spectroscopy, chemical ionization, and chemical sensing are used to measure and detect ammonia gas from exhaled breath. These methods and techniques are discussed in terms of their response time and the minimum concentration detectable. Furthermore, the benefits and importance of these methods and their limitation and drawback are highlighted.

  16. Exhale fluctuation in respiratory-gated radiotherapy of the lung: a pitfall of respiratory gating shown in a synchronized internal/external marker recording study.

    PubMed

    Nishioka, Seiko; Nishioka, Takeshi; Kawahara, Masaki; Tanaka, Shigeru; Hiromura, Tadao; Tomita, Kazuo; Shirato, Hiroki

    2008-01-01

    For optimal respiratory-gated radiotherapy, exhale fluctuation was assessed by monitoring internal fiducials in a synchronized internal/external marker detection system. Synchronized internal/external position data were collected during the entire course of treatments for 12 lung patients with 24 fiducials. Baseline was determined in the exhale phase during pre-treatment observation time, and a gating level of external waves was set in each treatment session in a simulation of respiratory-gated radiotherapy. Patients were treated under a real-time tumor-tracking (RTRT) system with an external (abdominal) respiratory motion detector. In the simulation, external gating windows were defined as those below the 30% amplitude level (i.e., imaginary beams would be triggered when part of the respiratory wave falls into this window). Exhale fluctuation (EF) was defined as the phenomenon in which the lowest point of the external wave crossed downward past the pre-determined baseline. Gating efficiency (GE) was defined as the ratio between the amount of gate-ON time and the total treatment time. EF occurred in 18.4% of total measurements. EF varied depending on the patient, fiducial sites, and treatment session. The mean incidence of EF for each patient varied from 2.9% to 37.5% (18.4+/-9.9). The EF magnitude was 0.2-12.2 mm in the left-right direction, 0.7-12.7 mm in the cranio-caudal direction, and 0.4-9.7 mm in the anterior-posterior direction. Total fiducial movement was 0.5-28.7 mm. GE was 36.1-69.2% (55.4+/-11.0). EF magnitude correlated with total fiducial movement. This study showed that EF is not a rare phenomenon and needs to be taken into consideration for individualized precise 4D radiotherapy.

  17. Laboratory facility to create reference radon + thoron atmosphere under dynamic exposure conditions.

    PubMed

    Pressyanov, D; Mitev, K; Georgiev, S; Dimitrova, I; Kolev, J

    2017-01-01

    Radon ((222)Rn) and thoron ((220)Rn) levels in the environment are typically subject to significant random and systematic variations. Creation in the laboratory of reproducible and controlled exposure conditions close to that in the real environment can be useful for testing (222)Rn and (220)Rn detectors and for research. In this report the design and performance of a novel laboratory facility with such functionality is presented. The facility allows the exposure of detectors under controlled dynamic as well as static activity concentrations of (222)Rn and (220)Rn (pure and mixed) and temperature. The temperature is measured and regulated within -15 °C ÷ +60 °C by a dedicated programmable thermostat. Different reference activity concentrations in the exposure vessel are made by regulating the flow-rate of the air that flushes (222)Rn/(220)Rn activity from the sources towards the exposure vessel. Reference atmospheres that contain (222)Rn, (220)Rn or a specified ratio of the two can be created. Pilot experiments that demonstrate the feasibility of the approach are presented. They include follow-up of a pre-defined temperature profile (in the range -5 °C ÷ +35 °C), test of the correspondence between planned and measured (222)Rn and (220)Rn activity concentrations, follow-up of a pre-defined dynamic profile of (220)Rn concentrations and test of the possibility to create mixed (220)Rn/(222)Rn atmospheres (experimentally checked for ratio of the activity concentrations from 0.27 to 4.5). The results from the experimental tests are in agreement with the values obtained by the developed theoretical model. The proposed approach can be used to plan and create stationary and dynamic reference exposure conditions that are close to the real exposure regimes in the environment.

  18. The relationships among Dermatophagoides pteronyssinus exposure, exhaled nitric oxide, and exhaled breath condensate pH levels in atopic asthmatic children.

    PubMed

    Yan, Dah-Chin; Chung, Fen-Fang; Lin, Syh-Jae; Wan, Gwo-Hwa

    2016-09-01

    This study examined seasonal changes in indoor Dermatophagoides pteronyssinus 1 (Der p 1)/Blattella germanica 1 (Bla g 1) antigen concentrations in the homes of atopic asthmatic and atopic nonasthmatic children. Possible associations between environmental allergen exposure and levels of exhaled breath indices were also evaluated.A total of 38 atopic children were recruited for this cross-sectional study: 22 were asthmatic and 16 were nonasthmatic. Home visits were conducted for indoor air and dust sampling each season. Exhaled nitric oxide (eNO)/spirometric measurements were taken and exhaled breath condensate (EBC) was collected after sampling of the domestic environment.The highest Der p 1 concentrations were on the top of mattresses in the homes of recruited children. The floors of kitchens and living rooms had the highest Bla g 1 concentrations in the homes of atopic asthmatic children. A positive correlation was found between Der p 1 exposure of mattress, bedroom floor, and living room floor and eNO levels in the atopic asthmatic children. The Der p 1 concentrations on the surfaces of mattress and bedroom floor were positively related to high eNO levels in the atopic asthmatic children after adjusting for season. No association was found between Der p 1 exposure and EBC pH values in the recruited children.A positive correlation was found between Der p 1 exposure and high eNO levels in atopic asthmatic children, especially in Der p 1 exposure of mattress and bedroom floor.

  19. The relationships among Dermatophagoides pteronyssinus exposure, exhaled nitric oxide, and exhaled breath condensate pH levels in atopic asthmatic children

    PubMed Central

    Yan, Dah-Chin; Chung, Fen-Fang; Lin, Syh-Jae; Wan, Gwo-Hwa

    2016-01-01

    Abstract This study examined seasonal changes in indoor Dermatophagoides pteronyssinus 1 (Der p 1)/Blattella germanica 1 (Bla g 1) antigen concentrations in the homes of atopic asthmatic and atopic nonasthmatic children. Possible associations between environmental allergen exposure and levels of exhaled breath indices were also evaluated. A total of 38 atopic children were recruited for this cross-sectional study: 22 were asthmatic and 16 were nonasthmatic. Home visits were conducted for indoor air and dust sampling each season. Exhaled nitric oxide (eNO)/spirometric measurements were taken and exhaled breath condensate (EBC) was collected after sampling of the domestic environment. The highest Der p 1 concentrations were on the top of mattresses in the homes of recruited children. The floors of kitchens and living rooms had the highest Bla g 1 concentrations in the homes of atopic asthmatic children. A positive correlation was found between Der p 1 exposure of mattress, bedroom floor, and living room floor and eNO levels in the atopic asthmatic children. The Der p 1 concentrations on the surfaces of mattress and bedroom floor were positively related to high eNO levels in the atopic asthmatic children after adjusting for season. No association was found between Der p 1 exposure and EBC pH values in the recruited children. A positive correlation was found between Der p 1 exposure and high eNO levels in atopic asthmatic children, especially in Der p 1 exposure of mattress and bedroom floor. PMID:27684812

  20. Fraction of exhaled nitric oxide in healthy elderly Tunisian subjects.

    PubMed

    Sfaxi, Ines; Ben Saad, Helmi; Rouatbi, Sonia

    2015-09-05

    Exhaled-fraction-of-nitric-oxide (FeNO) norms are absent in healthy elderly North-African subjects. i) to identify FeNO influencing factors of elderly Tunisians older 50 years and more; ii) to assess the applicability of some published FeNO norms for elderly in local population; iii) to set-up FeNO norms and to prospectively evaluate their validity in two elderly validation-groups (healthy and asthmatic subjects). A convenience sample of healthy and asthmatic elderly Tunisians was recruited. Subjects responded to a medical questionnaire and then FeNO levels were measured by an online method (Medisoft, Sorinnes (Dinant), Belgium). Clinical, anthropometric and spirometric data were collected. Three groups of subjects were identified: group I (healthy-elderly; n = 100, 57 females); group II (healthy-validation; n = 17, 4 females) and group III (asthmatic-validation; n = 10, 9 females). ANOVA was performed to compare the three groups' data. No significant factor, among those evaluated, influenced Tunisian elderly FeNO values. The available published FeNO norms did not reliably predict FeNO in Tunisian elderly population. The mean ± SD (minimum-maximum) of FeNO (ppb) for group I was 14 ± 6 (3-34). For Tunisian people, each elderly FeNO value higher than 34 ppb will be considered as abnormal. There was no statistical significant difference between FeNO (ppb) mean values of group I and groups II (15 ± 8) or III (18 ± 13). No subject of group II had a FeNO value higher than 34 ppb. Thirty percent of group III subjects had a FeNO value higher than 34 ppb. In practice, FeNO value of more than 34 ppb is considered abnormal in elderly Tunisian population. Copyright © 2015. Published by Elsevier Inc.

  1. Analysis of volatile organic compounds in exhaled breath to diagnose ventilator-associated pneumonia.

    PubMed

    Schnabel, Ronny; Fijten, Rianne; Smolinska, Agnieszka; Dallinga, Jan; Boumans, Marie-Louise; Stobberingh, Ellen; Boots, Agnes; Roekaerts, Paul; Bergmans, Dennis; van Schooten, Frederik Jan

    2015-11-26

    Ventilator-associated pneumonia (VAP) is a nosocomial infection occurring in the intensive care unit (ICU). The diagnostic standard is based on clinical criteria and bronchoalveolar lavage (BAL). Exhaled breath analysis is a promising non-invasive method for rapid diagnosis of diseases and contains volatile organic compounds (VOCs) that can differentiate diseased from healthy individuals. The aim of this study was to determine whether analysis of VOCs in exhaled breath can be used as a non-invasive monitoring tool for VAP. One hundred critically ill patients with clinical suspicion of VAP underwent BAL. Before BAL, exhaled air samples were collected and analysed by gas chromatography time-of-flight mass spectrometry (GC-tof-MS). The clinical suspicion of VAP was confirmed by BAL diagnostic criteria in 32 patients [VAP(+)] and rejected in 68 patients [VAP(-)]. Multivariate statistical comparison of VOC profiles between VAP(+) and VAP(-) revealed a subset of 12 VOCs that correctly discriminated between those two patient groups with a sensitivity and specificity of 75.8% ± 13.5% and 73.0% ± 11.8%, respectively. These results suggest that detection of VAP in ICU patients is possible by examining exhaled breath, enabling a simple, safe and non-invasive approach that could diminish diagnostic burden of VAP.

  2. Exhaled nitric oxide decreases upon acute exposure to high-altitude hypoxia.

    PubMed

    Brown, Daniel E; Beall, Cynthia M; Strohl, Kingman P; Mills, Phoebe S

    2006-01-01

    Nitric oxide (NO) is a vasodilator that plays a role in blood flow and oxygen delivery. Acute hypoxia down regulates NO synthesis, a response that may exacerbate hypoxic stress by decreasing blood flow. This study was designed to test the hypotheses that pulmonary NO decreases upon acute exposure to high-altitude hypoxia and that relatively low levels of NO at altitude are associated with greater stress as reflected in more symptoms of acute mountain sickness (AMS). A sample of 47 healthy, adult, nonsmoking, sea-level residents provided measurements at sea level, at 2,800 m, and at 0-, 2-, and 3-h exposure times at 4,200 m altitude on Mauna Kea, Hawaii. Measurements were made of exhaled NO, oxygen saturation of hemoglobin, heart rate, and reported symptoms of AMS. The partial pressure of NO concentration in exhaled breath decreased significantly from a sea level mean of 4.2 nmHg to 3.8 nmHg at 2,800 m and 3.4 nmHg at 4,200 m. NO concentration in exhaled breath did not change significantly over a 3-h exposure at 4,200 m and recovered to pre-exposure baseline upon return to sea level. There was no significant association between the level of NO exhaled and the number of self-reported symptoms of AMS during this brief exposure. Am. J. Hum. Biol. 18:196-202, 2006. (c) 2006 Wiley-Liss, Inc.

  3. Exhaled breath malondialdehyde as a matter of effect of exposure to airpollution in children with asthma

    EPA Science Inventory

    BACKGROUND: Assessment of the adverse effects of oxidative stress related to air pollution is limited by the lack of biological markers of dose to the lungs. OBJECTIVE: We evaluated the use of exhaled breath condensate (EBC) malondialdehyde as a biomarker of exposure to traffic-r...

  4. A REVIEW OF THE US EPA'S SINGLE BREATH CANISTER (SBC) METHOD FOR EXHALED VOLATILE ORGANIC BIOMARKERS

    EPA Science Inventory

    Exhaled alveolar breath can provide a great deal of information about an individual?s health and previous exposure to potentially harmful xenobiotic materials. Because breath can be obtained noninvasively and its constituents directly reflect concentrations in the blood, its us...

  5. 42 CFR 84.77 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Inhalation and exhalation valves; minimum requirements. 84.77 Section 84.77 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  6. 42 CFR 84.77 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Inhalation and exhalation valves; minimum requirements. 84.77 Section 84.77 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  7. 42 CFR 84.120 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Inhalation and exhalation valves; minimum requirements. 84.120 Section 84.120 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY...

  8. 42 CFR 84.77 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Inhalation and exhalation valves; minimum requirements. 84.77 Section 84.77 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  9. 42 CFR 84.120 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Inhalation and exhalation valves; minimum requirements. 84.120 Section 84.120 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY...

  10. 42 CFR 84.120 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Inhalation and exhalation valves; minimum requirements. 84.120 Section 84.120 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY...

  11. 42 CFR 84.77 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Inhalation and exhalation valves; minimum requirements. 84.77 Section 84.77 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES...

  12. 42 CFR 84.120 - Inhalation and exhalation valves; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Inhalation and exhalation valves; minimum requirements. 84.120 Section 84.120 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND